RU2549893C2 - Catalyst for producing ethanol by hydrogenating acetic acid, containing platinum-tin on silica support - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing ethanol by reducing acetic acid, which includes passing a gaseous stream containing hydrogen and acetic acid in vapour phase with molar ratio of oxygen to acetic acid of at least 4:1, at temperature of about 225°C to 300°C over a hydrogenation catalyst containing platinum and tin, dispersed on a modified substrate. Said modified substrate includes substrate material and an effective amount of a substrate modifier selected from a group consisting of metasilicates of alkali-earth metals, precursors thereof and mixtures thereof.

EFFECT: invention enables to carry out the method with high selectivity, high activity and longer service life of the catalyst.

12 cl, 12 dwg, 5 tbl, 16 ex

Description

Cross reference to related applications

This application claims the priority of US application No. 12/588727, filed October 26, 2009, the contents of which are incorporated into this description by reference.

FIELD OF THE INVENTION

The present invention generally relates to a controlled catalyst for the hydrogenation of carboxylic acids, in particular acetic acid, and an easily adaptable method for the hydrogenation of acetic acid, in which the proportion of ethanol relative to ethyl acetate and acetaldehyde can vary with each change in the catalyst to adapt to changing commercial conditions. More specifically, the present invention relates to a catalyst for the gas-phase hydrogenation of carboxylic acids, in particular acetic acid, for the production of various products, including the corresponding alcohols, esters and aldehydes, especially ethanol. These catalysts have excellent activity and selectivity for the specified range of products.

State of the art

There has long been a need for a cost-effective method of converting acetic acid to ethanol, which can be used on its own or subsequently converted to ethylene, which is an important industrially produced raw material, as it can be converted to vinyl acetate and / or ethyl acetate or any product from a wide range other chemical products. For example, ethylene can be converted into many polymeric and monomeric products. Fluctuations in the prices of natural gas and crude oil are also reflected in the fluctuation of prices for the ethylene produced in the traditional way, from oil or natural gas, which makes the need for alternative sources of ethylene the greater, the higher the oil price.

Catalytic methods for the reduction of alkanoic acids and other compounds containing a carbonyl group of compounds have been well studied and many combinations of catalysts, supports, and operating conditions are described in the literature. The reduction of various carboxylic acids on metal oxides is reviewed by T. Yokoyama et al. in Fine chemicals through heterogeneous catalysis. Carboxylic acids and derivatives. " Chapter 8.3.1 summarizes some of the results of efforts to develop hydrogenation catalysts for various carboxylic acids. (Yokoyama, T .; Setoyama, T. “Carboxylic acids and derivatives” in “Fine chemicals through heterogeneous catalysis, 2001, 370-379.)

Research Series M.A. Vannice et al. is devoted to the conversion of acetic acid on various heterogeneous catalysts (Rachmady, W .; Vannice, M.A .; J. Catal. 2002, 207, 317-330).

The reduction in the vapor phase of acetic acid with hydrogen over iron both on a substrate and without a substrate is described in a separate study. (Rachmady, W .; Vannice, M.A .; J. Catal. 2002, 208, 158-169).

Further information on the surface of catalyst particles and organic intermediates is described in Rachmady, W .; Vannice, M.A .; J. Catal. 2002, 208, 170-179.

Additionally studied the hydrogenation of acetic acid in the vapor phase on a family of Pt-Fe catalysts on a substrate, see Rachmady, W .; Vannice, M.A .; J. Catal. 2002, 209, 87-98 and Rachmady, W .; Vannice, M.A .; J. Catal. 2000, 192, 322-334.

For various publications regarding the selective hydrogenation of unsaturated aldehydes, see (Djeboua, F .; Benachour, D .; Touroude, R. Applied Catalyst A: General 2005, 282, 123-133; Liberkova, J .; Tourounde, RJ Mol. Catal . 2002, 180, 221-230; Rodrigues, EL; Bueno, JMC Applied Catalyst A: General 2004, 257, 210-211; Ammari, F .; Lamotte, J .; Touroude, RJCatal. 2004, 221, 32- 42; Ammari, F .; Milone, C .; Touroude, RJ Catal. 2005, 235, 1-9; Consonni, M .; Jokic, D .; Murzin, D, Y .; Touroude, RJCatal. 1999, 188 , 165-175; Nitta, Y .; Ueno, K .; Imanaka, T .; Applied Catal. 1989, 56, 9-22).

Studies on activity and selectivity on cobalt, platinum, and tin catalysts during the selective hydrogenation of crotonic aldehyde to an unsaturated alcohol are described in R. Touroude et al. (Djeboua, F .; Benachour, D .; Touroude, R. Applied Catalyst A: General 2005, 282, 123-133, as well as Liberkova, J .; Tourounde, RJ Mol. Catal. 2002, 180, 221-230) as well as K. Lazar et al. (Lazar, K .; Rhodes, W.D .; Borbath, I .; Hegedues, M .; Margitfalvi, 1. L. Hyperfine Interactions 2002, 1391140, 87-96).

M. Santiago et al. (Santiago, M.A.N .; Sanchez-Castillo, M.A .; Cortright, R. D.; Dumesic, 1. A. J. Catal 2000, 193, 16-28) discuss microcalorimetric measurements, infrared spectral analysis and reaction kinetics measurements in combination with quantum chemical calculations.

Catalytic activity against hydrogenation of acetic acid is also described for heterogeneous systems with rhenium and ruthenium. (Ryashentseva, M.A .; Minachev, K.M .; Buiychev, B.M .; Ishchenko, V.M. Bull. Acad. Sci. USSR 1988, 2436-2439).

US Pat. No. 5,149,680, to Kitson et al., Describes a method for the catalytic hydrogenation of carboxylic acids and their anhydrides to alcohols and / or esters using catalysts based on platinum group metal alloys. US Pat. No. 4,777,303, to Kitson et al., Describes a process for producing alcohols by hydrogenating carboxylic acids. In US patent No. 4804791, in the name of Kitson et al., Describes another method for the production of alcohols by hydrogenation of carboxylic acids. See also US patents 5061671, 4990655, 4985572 and 4826795.

Manilowski et al. (Bull. Soc. Chem. Belg. (1985), 94 (2), 93-5) consider catalysts for the reaction of acetic acid on low valent titanium heterogenized on such support materials as silicon dioxide (SiO ₂ ) or titanium oxide (TiO ₂ )

Ruthenium-tin / silica bimetallic catalysts were prepared by the reaction of tetrabutyltin with ruthenium dioxide on a silica support. (Loessard et al., Stadies in Surface Science and Catalyst (1989), Volume Date 1988, 48 (Struct. React.Surf.), 591-600.)

The catalytic reduction of acetic acid has also been studied, for example, by Hindermann et al. (Hindermann et al., J. Chem. Res., Synopses (1980), (11), 373) describe the catalytic reduction of acetic acid on iron and alkali-promoted iron.

Existing methods have many disadvantages that reduce their economic efficiency, including: (i) the catalysts do not have the necessary selectivity for the formation of ethanol; (ii) catalysts that are possibly too expensive and / or non-selective with respect to the formation of ethanol and contribute to the formation of undesirable by-products; (iii) excessive operating temperature and pressure; and / or (iv) insufficient catalyst life.

SUMMARY OF THE INVENTION

The inventors found that when reducing acetic acid on a platinum-tin catalyst dispersed on a modified stabilized silica substrate containing an effective amount of a substrate modifier selected from the group consisting of: (i) alkaline earth metal oxides, (ii) alkali metal oxides, ( iii) alkaline earth metal metasilicates, (iv) alkali metal metasilicates, (v) zinc oxide, (vi) zinc metasilicate and (vii) precursors of any of (i) to (vi), and mixtures of any of (i) to (vii) , by skipping boiling a gaseous stream containing hydrogen and acetic acid in the vapor phase at a molar ratio of hydrogen to acetic acid of at least about 4: 1, at a temperature of from about 125 ° C to 350 ° C, more preferably from about 225 ° C up to 300 ° C, even more preferably from about 250 ° C to 300 ° C above this catalyst, it is possible to achieve high selectivity of conversion to ethanol if the amount and oxidation state of platinum and tin, as well as the ratio of platinum, tin and modified stabilized silica substrate adjust to a described herein. In one aspect of the present invention, the authors counteract the influence of the centers of Bransted acids present on the surface of a silica substrate by a substrate modifier selected as described above. In another aspect, the substrate modifiers described above are effective in preventing an excessive decrease in catalyst activity and selectivity over a period of up to 168, 336 or even 500 hours at 275 ° C. in the presence of an acetic acid vapor stream. In another aspect of the invention, the substrate modifier is effective in suppressing the formation of ethyl acetate, which leads to high selectivity for the formation of ethanol, optionally accompanied by low selectivity for the conversion of acetic acid into extremely undesirable by-products such as alkanes. Preferably, the substrate modifier is selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds. The most preferred substrate modifier is calcium metasilicate.

The authors found that when reducing acetic acid on a platinum-tin catalyst dispersed on a substrate essentially of basic calcium / silica metasilicate, by passing a gaseous stream containing hydrogen and acetic acid in the vapor phase, with a molar ratio of hydrogen to acetic acid at least about 4: 1, at a temperature of from about 125 ° C to 350 ° C, more preferably from about 225 ° C to 300 ° C, even more preferably from about 250 ° C to 300 ° C above this catalyst, you can achieve high selectivity of conversion to ethanol if the amount and degree of oxidation of platinum and tin, as well as the ratio of platinum to tin and the acidity of the substrate, calcium metasilicate / silica are adjusted as described in the present description. In particular, when using the preferred catalysts and methods of the present invention, at least 80% of the converted acetic acid is converted to ethanol, and less than 4% of the acetic acid is converted to compounds other than compounds selected from the group consisting of ethanol, acetaldehyde, ethyl acetate, ethylene and mixtures thereof. In preferred methods, platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; however, tin is present in an amount of at least 0.5 to 10% by weight of the catalyst; preferably, the surface area of the substrate is at least about 100 m ² / g, more preferably about 150 m ² / g, even more preferably at least about 200 m ² / g, most preferably at least about 250 m ² / g; the molar ratio of tin to platinum group metal is preferably from about 1: 2 to about 2: 1, more preferably from about 2: 3 to about 3: 2, even more preferably from about 5: 4 to about 4: 5 most preferably from about 9:10 to about 10: 9. In many cases, the substrate contains calcium silicate in an amount effective to balance the centers of Bransted acids resulting from the presence of residual alumina in the silica; usually from about 1% to about 10% of the mass. calcium silicate is sufficient to ensure that the substrate is substantially neutral or basic in nature. In one particularly preferred embodiment of the invention, platinum is present in the hydrogenation catalyst in an amount of at least about 0.75%, more preferably 1% by weight .; the molar ratio of tin to platinum is from about 5: 4 to about 4: 5; the substrate contains at least about 2.5% to about 10% of the mass. calcium silicate.

One aspect of many embodiments of the present invention is that when using a space velocity of more than about 1000 h ^-1 , 2500 h ^-1 and even more than 5000 h ^-1 , at least 90% of the converted acetic acid is converted to ethanol, and less 2% of acetic acid is converted into compounds other than compounds selected from the group consisting of ethanol, acetaldehyde, ethyl acetate, ethylene and mixtures thereof. In many embodiments of the present invention, the formation of alkanes is small, usually less than 2%, often less than 1%, in many cases, less than 0.5% of the acetic acid passing over the catalyst is converted to alkanes of low value, except when used as fuel or synthesis gas.

In another aspect of the present invention, alkanoic acids are hydrogenated by passing a gaseous stream containing hydrogen and alkanoic acid in the vapor phase, with a molar ratio of hydrogen to alkanoic acid of at least about 2: 1, at a temperature of from about 125 ° C. to 350 ° C. above a hydrogenation catalyst containing: a platinum group metal selected from the group consisting of platinum, palladium and mixtures thereof, on a silica substrate selected from the group consisting of silicon dioxide, calcium metasilicate and silicon dioxide I promoted calcium metasilicate; and a promoter selected from the group consisting of tin, rhenium and mixtures thereof, wherein the silica substrate is optionally promoted with a promoter selected from the group consisting of alkali metals; alkaline earth elements and zinc, in an amount of 1-5% by weight of the catalyst; a redox promoter selected from the group consisting of WO ₃ , MoO ₃ , Fe ₂ O ₃ and Cr ₂ O ₃ , in an amount of 1-50% by weight of the catalyst; an acidity modifier selected from the group consisting of TiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ and Al ₂ O ₃ , in an amount of 1-50% by weight of the catalyst, while the acidity of the substrate is controlled so that less 4, preferably less than 2, most preferably less than about 1% alkanoic acid is converted to alkane. In many cases, at least one of the elements — platinum and palladium — is present in an amount of 0.25% to 5% by weight of the catalyst; the total amount of platinum and palladium present in the catalyst is at least 0.5% by weight of the catalyst; the total amount of rhenium and tin present is at least 0.5 to 10% by weight. As in the case of catalysts containing platinum and tin on a basic silica support, in this method the amount and oxidation state of platinum group metals, rhenium and tin promoters, as well as the ratio of the number of moles of the platinum group metal to the total number of moles of rhenium and tin present, and acidity the silica support is adjusted so that at least 80% of the converted acetic acid is converted to a compound selected from the group consisting of aliphatic alcohol and alkyl acetate, while less than 4% ksusnoy acid is converted into a compound other than a compound selected from the group consisting of the corresponding aliphatic alcohols, alkyl acetates, and mixtures thereof. Preferably, at least one of the elements — platinum and palladium — is present in an amount of from 0.5% to 5% by weight of the catalyst; the total amount of platinum and palladium present is at least 0.75% to 5% by weight of the catalyst. Preferably, alkanoic acid is acetic acid, and the total amount of tin and rhenium present is at least 1.0% by weight of the catalyst, while the amount and oxidation state of the platinum group metals, rhenium and tin promoters, and the molar ratio of platinum metals the rhenium and tin promoter groups and the acidity of the silica support are adjusted so that at least 80% of the converted acetic acid is converted to ethanol or ethyl acetate, and less than 4% of the acetic acid is converted to eniya other than a compound selected from the group consisting of ethanol, acetaldehyde, ethyl acetate, ethylene and mixtures thereof. Preferably, the total mass of rhenium and tin present is about 1-10% by weight of the catalyst; whereas the ratio of the number of moles of metal of the platinum group to the total number of moles of rhenium and tin is from about 1: 2 to about 2: 1.

In another aspect, the present invention relates to a method for hydrogenation of acetic acid, comprising passing a gaseous stream containing hydrogen and acetic acid in the vapor phase, with a molar ratio of hydrogen to acetic acid of at least about 4: 1, at a temperature of from about 225 ° C. up to 300 ° C above the hydrogenation catalyst, consisting essentially of metal components dispersed on an oxide substrate, while the hydrogenation catalyst has the composition:

Pt _v Pd _w Re _x Sn _y Ca _p Si _q O _r ,

where the ratio v: y is from 3: 2 to 2: 3; and / or the ratio w: x is from 1: 3 to 1: 5, p and q are selected so that p: q is from 1:20 to 1: 200, with r selected so that the valence requirements are satisfied, and v and w are chosen so that

≤0,05.0.005≤ $$\frac{(3.25v+1.75w)}{q}$$

≤0.05.

In this aspect, the conditions of the method and the values of v, w, x, y, p, q and r are preferably selected such that at least 90% of the converted acetic acid is converted to a compound selected from the group consisting of ethanol and ethyl acetate while less than 4% of acetic acid is converted to alkanes. In many embodiments of the present invention, p is selected taking into account any small amount of impurities present so that there are essentially no active Bransted acid sites on the surface of the substrate.

In yet another aspect, the present invention relates to a method for producing ethanol by reducing acetic acid, comprising passing a gaseous stream containing hydrogen and acetic acid in the vapor phase, with a molar ratio of hydrogen to acetic acid of at least about 4: 1, at a temperature of about from 225 ° C to 300 ° C above the hydrogenation catalyst, consisting essentially of metal components dispersed on an oxide substrate, while the specified hydrogenation catalyst has the composition:

Pt _v Pd _w Re _x Sn _y Al _z Ca _p Si _q O _r ,

where the ratio v: y is from 3: 2 to 2: 3; the w: x ratio is from 1: 3 to 1: 5, while p and z and the relative position of aluminum and calcium atoms are controlled so that the centers of the Bransted acids present on the surface are balanced by calcium silicate; p and q are chosen so that p: q is from 1:20 to 1: 200, with r chosen so that the valency requirements are satisfied, and v and w are chosen so that

≤0,05.0.005≤ $$\frac{(3.25v+1.75w)}{q}$$

≤0.05.

Preferably, in this aspect, the hydrogenation catalyst has a surface area of at least about 100 m ² / g, and z and p≥z. In many embodiments of the present invention, p is selected taking into account any small amount of impurities present to also ensure that there are essentially no Bransted acid active sites on the surface of the substrate that are believed to facilitate the conversion of ethanol to ethyl acetate.

In another aspect, the present invention relates to a method for hydrogenation of acetic acid, comprising passing a gaseous stream containing hydrogen and acetic acid in the vapor phase, with a molar ratio of hydrogen to acetic acid of at least about 4: 1, at a temperature of from about 225 ° C. up to 300 ° C above a hydrogenation catalyst containing: a platinum group metal selected from the group consisting of platinum and mixtures of platinum and palladium on a silica substrate selected from the group consisting of silicon dioxide and dioxide silicon, promoted with calcium metasilicate in an amount of up to about 7.5%, where the amount of platinum group metal present is at least about 2.0%, the amount of platinum present is at least about 1.5%; and a metal promoter selected from the group consisting of rhenium and tin is present in an amount of 1-2% by weight of the catalyst, while the molar ratio of platinum to the metal promoter is from about 3: 1 to 1: 2; the silica support is optionally promoted by a second promoter selected from the group consisting of: a donor promoter selected from the group consisting of alkali metals; alkaline earth elements and zinc, in an amount of 1-5% by weight of the catalyst; a redox promoter selected from the group consisting of WO ₃ , MoO ₃ , Fe ₂ O ₃ and Cr ₂ O ₃ , in an amount of 1-50% by weight of the catalyst; an acidity modifier selected from the group consisting of TiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ and Al ₂ O ₃ , in an amount of 1-50% by weight of the catalyst; and their combinations.

In preferred aspects of the invention, the molar ratio of the metal promoter to the platinum group metal is from about 2: 3 to about 3: 2, more preferably from about 5: 4 to about 4: 5, most preferably from about 9:10 to about 10 : 9, wherein the surface area of the silica substrate is at least about 200 m ² / g, and the amount of sodium silicate is sufficient so that the surface of the substrate is substantially basic. In some cases, the use of calcium silicate can be controlled so that the number of moles of Branstead acids present on the surface of the substrate does not exceed the number of moles of Bransted acids present on the surface of Saint-Gobain NorPro SS61138 silica; in other cases, the silica used may be high purity fumed silica, characterized by a low content of alumina or other impurities. In many cases, such silicon oxides will contain more than 99% silica, more preferably more than 99.5% silica, most preferably more than 99.7% silica. In many embodiments of the present invention, either by adjusting the purity of the silica or by balancing the centers of the Bransted acids present on the surface of the substrate with calcium silicate or one of the other suitable stabilizing modifiers described herein, the available number of moles of centers Bransted acids present on the surface of the substrate does not exceed the number of moles of Bransted acid centers present on the surface of Saint-Gobain N silica orPro SS61138 is preferably less than half, more preferably less than 25%, even more preferably less than 10% of the number of moles of Bransted acid sites present on the surface of Saint-Gobain NorPro SS61138 silica. The number of acid sites on the surface of the substrate can be determined using titration with pyridine, following the procedures described in:

(1) F. Delannay, Ed., "Characterization of Heterogeneous Catalysts"; Chapter III: Measurement of Acidity of Surfaces, p. 370-404; Marcel Dekker, Inc., N. Y. 1984.

(2) C.R. Brundle, C.A. Evans, Jr., S. Wilson, L.E. Fitzpatrick, Eds., "Encyclopedia of Materials Characterization"; Chapter 12.4: Physical and Chemical Adsorption Measurements of Solid Surface Areas, p. 736-744; Butterworth-Heinemann, MA 1992.

(3) G.A. Olah, G.K. Sura Prakask, Eds, "Superacids"; John Wiley & Sons, N. Y. 1985.

In this description and the claims, unless the context indicates otherwise, the method described in F. Delannay, Ed., “Characterization of Heterogeneous Catalysts” should be used when measuring the surface acidity or the number of acid sites on it; Chapter III: Measurement of Acidity of Surfaces, p. 370-404; Marcel Dekker, Inc., N, Y. 1984.

In a more preferred case, the surface area of the silica support is at least about 250 m ² / g, and the number of moles of available Bransted acid centers on its surface does not exceed half the number of moles of Bransted acid centers present on the surface of Saint-Gobain NorPro silica SS61138, wherein, the hydrogenation is carried out at a temperature of from about 250 ° C to 300 ° C.

As will be apparent to those skilled in the art upon reading this description, catalyst substrates other than silica substrates described above can be used in some embodiments of the invention, provided that the components are selected so that the catalyst system is properly active, selective and stable under the applicable process conditions. Suitable substrates may include stable metal oxide substrates or ceramic-based substrates, as well as molecular sieves, including zeolites. In addition, carbon substrates may be used in some embodiments of the invention, as described in US Pat. No. 5,149,680, to Kitson et al., In col. 2, line 64 count. 4, line 22, the description of which is incorporated into this description by reference.

In cases where it is necessary to obtain mixtures of ethanol and ethyl acetate at the same time, in many embodiments of the present invention, the hydrogenation catalyst may comprise: palladium on a silica support selected from the group consisting of silicon dioxide and silicon dioxide, promoted with calcium metasilicate in an amount of up to about 7.5 %, where the amount of palladium present is at least about 1.5%; while the metal promoter is rhenium in an amount of from about 1% to 10% by weight of the catalyst, and the molar ratio of rhenium to palladium is from about 4: 1 to 1: 4, preferably from 2: 1 to 1: 3.

In cases where it is preferable to obtain mainly ethanol, in many embodiments of the present invention, the catalyst may consist essentially of platinum on a silica support consisting essentially of silicon dioxide promoted with calcium silicate in an amount of from about 3 to about 7.5%, where the amount of platinum present is at least about 1.0%, the tin promoter is present in an amount of about 1% to 5% by weight of the catalyst, the molar ratio of platinum to tin in many embodiments The present invention is approximately from 9:10 to 10: 9. In some cases, a minor amount of another metal of the platinum group, most often palladium, may be added to the catalytically active metal of this composition. In many embodiments, the amount of platinum group metal present is at least about 2.0%, the amount of platinum present is at least about 1.5%, preferably 2.5 to 3.5 weight percent platinum, the promoter-tin is present in an amount of from about 2% to 5% by weight of the catalyst, while the process is carried out at a temperature of from about 250 ° C to 300 ° C at GHSV (full hourly space velocity) of at least about 1000 h ^-1 and a pressure of at least 2 atm. The ratio of tin to platinum is preferably from 2: 3 to 3: 2, more preferably from 4: 5 to 5: 4, most preferably from 9:10 to 10: 9. In other embodiments of the invention in which it is preferable to obtain mainly ethanol, the catalyst may comprise platinum on a silica support consisting essentially of silica promoted with calcium silicate in an amount of from about 3 to about 7.5%, where the amount the platinum present is at least about 1.0%, the tin promoter is present in an amount of about 1% to 5% by weight of the catalyst, the molar ratio of platinum to tin in many embodiments of the present invention is ranges from approximately 9:10 to 10: 9.

In another aspect, the present invention relates to a particulate catalyst for hydrogenating alkanoic acids to the corresponding aliphatic alcohol, comprising: a platinum group metal selected from the group consisting of platinum, palladium and mixtures thereof, on a silica support selected from the group consisting of dioxide silicon and silicon dioxide, promoted with calcium metasilicate in an amount of from about 3.0 to about 7.5%, while the surface area of the silica substrate is at least about 150 m ² / g; and a tin promoter in an amount of from about 1% to 3% by weight of the catalyst, wherein the molar ratio of platinum to tin is from about 4: 3 to 3: 4, the composition and structure of the silica substrate are selected so that its surface is essentially the main one.

In another aspect, the present invention relates to a particulate hydrogenation catalyst consisting essentially of: a silica support on which a platinum group metal is selected, selected from the group consisting of platinum, palladium and mixtures thereof, with a promoter selected from the group consisting of tin, cobalt and rhenium, while the silica substrate has a surface area of at least about 175 m ² / g and is selected from the group consisting of silicon dioxide, calcium metasilicate and silicon dioxide, promoted metasilicate ohm calcium, where calcium metasilicate is located on its surface, while the surface of the silica substrate is essentially devoid of the free centers of Bransted acids that arise when aluminum oxide is not balanced by calcium. In those variants that are best suited for the simultaneous production of ethanol and ethyl acetate, the total mass of the platinum group metals present is from 0.5% to 2%, the amount of palladium present is at least 0.5%, the rhenium promoter is massive the ratio of rhenium to palladium is from 10: 1 to 2: 1, the amount of calcium metasilicate is from 3 to 90%.

In those embodiments that are best suited to produce ethanol with high selectivity, the total mass of platinum group metals present is from 0.5% to 2%, the amount of platinum present is at least 0.5%, the cobalt promoter is massive the ratio of cobalt to platinum is from 20: 1 to 3: 1, and the amount of calcium silicate is from 3 to 90%, in addition, to produce ethanol using a catalyst characterized by an increased service life, this hydrogenation catalyst contains from 2.5 to 3.5 mass percent of platinum, from 3% of the mass. up to 5% of the mass. tin dispersed on a fumed silica with a highly developed surface, characterized by a surface area of at least 200 m ² per gram, while said silica with a highly developed surface is promoted with an effective amount of calcium metasilicate to ensure that the surface, there are essentially no free centers of Bransted acids unbalanced by calcium metasilicate, the molar ratio of platinum to tin is from 4: 5 to 5: 4.

In another catalyst of the present invention, the total weight of the platinum group metal present is from 0.5 to 2%, the amount of palladium present is at least 0.5%, the promoter is cobalt, the mass ratio of cobalt to palladium is from 20: 1 to 3 : 1, the amount of calcium silicate is from 3 to 90%.

Another catalyst of the present invention is a hydrogenation catalyst containing: from 0.5 to 2.5 weight percent palladium, from 2% of the mass. up to 7% of the mass. rhenium, the mass ratio of rhenium to palladium is at least 1.5: 1.0, rhenium and palladium are dispersed on a silica substrate, where the silica substrate contains at least 80% calcium metasilicate.

The authors found that unexpectedly high activity and a long service life, combined with excellent selectivity for hydrogenation of acetic acid to ethanol, can be obtained using catalysts selected from the group consisting of:

(i) catalysts combining a platinum group metal selected from the group consisting of platinum, palladium and mixtures thereof, with tin or rhenium, on a silica support selected from the group consisting of silicon dioxide, calcium metasilicate and silicon dioxide, promoted with calcium metasilicate ;

(ii) catalysts combining palladium and rhenium on a silica support selected from the group consisting of silica, calcium metasilicate and silica promoted with calcium metasilicate, wherein the silica support is optionally promoted with a promoter in an amount of 1% to 5% selected from the group consisting of alkali metals, alkaline earth elements and zinc, while the promoter is preferably added to the catalytic composition in the form of corresponding nitrates or acetates, from these promoters highly preferred are potassium, cesium, calcium, magnesium, and zinc;

(iii) cobalt-promoted platinum on a highly developed silica substrate selected from the group consisting of silicon dioxide, calcium metasilicate and silicon dioxide promoted with calcium metasilicate; and

(iv) cobalt promoted palladium on a silica substrate with a highly developed surface selected from the group consisting of silicon dioxide, calcium metasilicate and silicon dioxide promoted with calcium metasilicate.

In another aspect, the present invention relates to a method for hydrogenation of alkanoic acids, comprising passing a gaseous stream containing hydrogen and alkanoic acid in the vapor phase, with a molar ratio of hydrogen to alkanoic acid of at least about 2: 1, at a temperature of from about 125 ° C. up to 350 ° C over a hydrogenation catalyst containing:

but. a platinum group metal selected from the group consisting of platinum, palladium and mixtures thereof, on a silica substrate selected from the group consisting of silicon dioxide, calcium metasilicate and silicon dioxide, promoted with calcium metasilicate; and

b. a promoter selected from the group consisting of tin and rhenium,

from. silica support, optionally promoted with a promoter selected from the group consisting of:

i. a promoter selected from the group consisting of alkali metals, alkaline earth elements and zinc, in an amount of 1-5% by weight of the catalyst;

ii. a redox promoter selected from the group consisting of WO ₃ , MoO ₃ , Fe ₂ O ₃ and Cr ₂ O ₃ , in an amount of 1-50% by weight of the catalyst; and

iii. an acidity modifier selected from the group consisting of TiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ and Al ₂ O ₃ , in an amount of 1-50% by weight of the catalyst.

Preferably, alkanoic acid is acetic acid, and platinum, if present, is present in an amount of from 0.5% to 5% by weight of the catalyst; palladium, if present, is present in an amount of from 0.25% to 5% by weight of the catalyst; the total amount of platinum and palladium is at least 0.5% by weight of the catalyst; tin is present in an amount of at least 0.5 to 5% with such a ratio of platinum to tin as described above.

In another aspect of the present invention, the surface area of the silica support is at least about 150 m ² / g, more preferably at least about 200 m ² / g, most preferably at least about 250 m ² / g. In more preferred embodiments, the silica support contains up to about 7.5% calcium metasilicate. In other embodiments, the silica support comprises up to about 90% calcium metasilicate. In all embodiments of the invention, it may be very useful to control the acidity of the support, in particular when it is necessary to obtain substantially pure ethanol. In the case where only silica is used as the substrate, it is very useful to take measures to ensure that the amount of alumina, which is a common contaminant of silica, is low, preferably up to 1%, more preferably up to 0.5%, most preferably up to 0.3% of the mass. In this sense, it is extremely preferable to use the so-called fumed silica, since it is generally available at a purity of more than 99.7%. In this specification, when high purity silica is mentioned, silica is meant in which acidic contaminants such as alumina are present in an amount of less than 0.3% by weight. In cases where silica promoted with calcium metasilicate is used, it is usually not necessary to comply with such strict limitations regarding the purity of the silica used as the substrate, although the presence of alumina is undesirable and is usually not specifically added.

In more preferred embodiments of the present invention, platinum, if present, is present in an amount of from 1% to 5% by weight of the catalyst; palladium, if present, is present in an amount of from 0.5% to 5% by weight of the catalyst; the total amount of platinum and palladium is at least 1% by weight of the catalyst.

In another preferred embodiment of the present invention, in which the substrate is essentially pure silica with a highly developed surface, preferably silica obtained by the pyrogenetic method, tin is present in an amount of 1% to 3% by weight of the catalyst, more preferably molar the ratio of tin to platinum group metal is from about 1: 2 to about 2: 1; even more preferably, the molar ratio of tin to platinum is from about 2: 3 to about 3: 2; most preferably, the molar ratio of tin to platinum is from about 5: 4 to about 4: 5. In cases where the substrate also contains a small amount of CaSiO ₃ or other stabilizing modifiers in the range of from about 2% to about 10%, more acidic impurities may be allowed, provided that they are balanced by an appropriate amount of a substantially basic stabilizing modifier.

In another aspect of the present invention, the method is preferably carried out at a temperature of from about 225 ° C to 300 ° C, more preferably from about 250 ° C to 300 ° C, wherein said hydrogenation catalyst comprises: a platinum group metal selected from the group consisting of platinum and mixtures of platinum and palladium on a silica substrate selected from the group consisting of silicon dioxide and silicon dioxide, promoted with calcium metasilicate in an amount of up to about 7.5%, where the amount of platinum group metal present s is at least about 2.0%, the amount of platinum present is at least about 1.5%; and a tin promoter in an amount of about 1-2% by weight of the catalyst, wherein the molar ratio of platinum to tin is from about 3: 1 to 1: 2; the silica support is optionally promoted with a promoter selected from the group consisting of: a promoter selected from the group consisting of alkali metals, alkaline earth elements and zinc, in an amount of 1-5% by weight of the catalyst; a redox promoter selected from the group consisting of WO ₃ , MoO ₃ , Fe ₂ O ₃ and Cr ₂ O ₃ , in an amount of 1-50% by weight of the catalyst; and an acidity modifier selected from the group consisting of TiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ and Al ₂ O ₃ , in an amount of 1-50% by weight of the catalyst.

In particularly preferred methods of the present invention, the alkanoic acid hydrogenation catalyst comprises: a platinum group metal selected from the group consisting of platinum and mixtures of platinum and palladium, on a silica substrate selected from the group consisting of highly pure silica with a highly developed surface and silicon dioxide with a highly developed surface promoted with calcium metasilicate in an amount of up to about 7.5%, where the amount of platinum group metal present is at least about 2.0%, the amount of platinum present is at least about 1.5%; and the amount of the tin promoter is about 1-5% by weight of the catalyst, while the molar ratio of platinum to tin is about 3: 2 to 2: 3. Preferably, high purity silica is obtained by a pyrogenic process, then tableted or granulated into a mold that is of sufficient density for use in a fixed catalyst bed. However, even in the case of using high-purity silicon dioxide, the presence of a stabilizing modifier, in particular calcium silicate, is believed to increase or stabilize the activity and selectivity of the catalyst over a long period, covering weeks or even months of industrial operation in the presence of acetic acid vapor at a temperature of about 275 ° C and a space velocity of 2500 h ^-1 or more. In particular, it is possible to achieve such a degree of stability that the activity of the catalyst will decrease by less than 10% over a period of a week (168 hours) or two (336 hours), or even more than 500 hours. In this regard, it should be noted that the catalysts of the present invention are fully suitable for commercial use on an industrial scale for the hydrogenation of acetic acid, in particular in the production of ethanol of high purity, as well as mixtures of ethyl acetate and ethanol.

In another aspect, the present invention relates to hydrogenation catalysts based on Group VIII metals (Fe, Co, Ni, Ru, Rh, Pd, Ir, Pt and Os) or other transition metals (namely, Ti, Zn, Cr, Mo and W ) on oxide substrates containing basic non-volatile stabilizer-modifiers on the surface or in the substrate itself in the form of oxides and metasilicates of alkaline earth metals, alkali metals, zinc, scandium, yttrium, precursors of these oxides and metasilicates, as well as their mixtures in quantities sufficient for: neutralization of acid centers, present on the surface of the substrate; imparting resistance to a change in shape (mainly due to, among other things, sintering, grain growth, migration of grain boundaries, migration of defects and dislocations, plastic deformation and / or other thermal changes in the microstructure) at temperatures used in the hydrogenation of acetic acid; or both.

In another embodiment of the method of the present invention, the catalyst is selected from:

(i) catalysts combining a platinum group metal selected from the group consisting of platinum, palladium and mixtures thereof, with tin or rhenium, on a silica support selected from the group consisting of silicon dioxide, calcium metasilicate and silicon dioxide, stabilized and modified calcium metasilicate;

(ii) catalysts combining palladium and rhenium on a silica support selected from the group consisting of calcium metasilicate and silicon dioxide promoted with calcium metasilicate, wherein the silica support is optionally promoted with a promoter in an amount of 1% to 5% selected from the group consisting of alkali metals, alkaline earth elements and zinc;

(iii) cobalt promoted platinum on a silica support selected from the group consisting of silica, calcium metasilicate and silica promoted with calcium metasilicate; and

(iv) cobalt promoted palladium on a silica support selected from the group consisting of silica, calcium metasilicate and silica promoted with calcium metasilicate.

Typically, a silica support includes a promoter selected from the group consisting of: stabilizer-modifiers, including alkali metal oxides and metasilicates; alkaline earth elements and zinc and their precursors, in an amount of 1-5% by weight of the catalyst; a redox promoter selected from the group consisting of: WO ₃ , MoO ₃ , Fe ₂ O ₃ and Cr ₂ O ₃ , in an amount of 1-50% by weight of the catalyst; an acidity modifier selected from the group consisting of TiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ and Al ₂ O ₃ in an amount of 1-50% by weight of the catalyst, while the presence of an acid modifier promotes the formation of ethyl acetate in combination with ethanol.

In another aspect, the present invention relates to a particulate catalyst for hydrogenating alkanoic acids to the corresponding aliphatic alcohol, comprising: a platinum group metal selected from the group consisting of platinum, palladium and mixtures thereof, on a silica support selected from the group consisting of dioxide silicon, silicon dioxide, promoted with calcium metasilicate in an amount of up to about 7.5%, and mixtures thereof, while the surface area of the silica substrate is at least about 150 m ² / g; and a tin promoter in an amount of from about 1% to 2% by weight of the catalyst, wherein the molar ratio of platinum to tin is from about 3: 2 to 3: 2, the silica substrate being optionally promoted with a promoter selected from the group consisting of: a promoter selected from the group consisting of alkali metals; alkaline earth elements and zinc, in an amount of 1-5% by weight of the catalyst; a redox promoter selected from the group consisting of: WO ₃ , MoO ₃ , Fe ₂ O ₃ and Cr ₂ O ₃ , in an amount of 1-50% by weight of the catalyst; and an acidity modifier selected from the group consisting of TiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ and Al ₂ O ₃ , in an amount of 1-50% by weight of the catalyst.

In an alternative embodiment, the present invention relates to a particulate hydrogenation catalyst consisting essentially of: a silica support on which a platinum group metal is dispersed, selected from the group consisting of platinum, palladium and mixtures thereof, with a promoter selected from group consisting of tin, cobalt and rhenium, thus, the silica support has a surface area of at least about 175 m ² / g and is selected from the group consisting of silica, calcium metasilicate, silica and Promoted calcium metasilicate; however, the silica substrate is optionally promoted with a promoter in an amount of from 1% to 5%, selected from the group consisting of alkali metals, alkaline earth elements and zinc, in an amount of 1-5% by weight of the catalyst; a redox promoter selected from the group consisting of: WO ₃ , MoO ₃ , Fe ₂ O ₃ and Cr ₂ O ₃ , in an amount of 1-50% by weight of the catalyst; and an acidity modifier selected from the group consisting of TiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ and Al ₂ O ₃ , in an amount of 1-50% by weight of the catalyst. In one of the more preferred embodiments of the present invention, the total mass of platinum group metals present is from 2% to 4%, the amount of platinum present is at least 2%, the tin promoter is, the mass ratio of platinum to tin is from 2: 3 to 3: 2, the amount of calcium metasilicate is from 3 to 7%. In another more preferred embodiment of the present invention, the total mass of platinum group metals present is from 0.5% to 2%, the amount of palladium present is at least 0.5%, the rhenium promoter is, the rhenium to palladium mass ratio is from 10 : 1 to 2: 1, the amount of calcium metasilicate is from 3 to 90%. In a third more preferred embodiment of the present invention, the total mass of platinum group metals present is from 0.5% to 2%, the amount of platinum present is at least 0.5%, the promoter is cobalt, the mass ratio of cobalt to platinum is from 20 : 1 to 3: 1, the amount of calcium silicate is from 3 to 90%. In a fourth more preferred embodiment of the present invention, the total mass of platinum group metals present is from 0.5% to 2%, the amount of palladium present is at least 0.5%, the promoter is cobalt, the mass ratio of cobalt to palladium is from 20 : 1 to 3: 1, the amount of calcium silicate is from 3 to 90%.

Brief Description of the Figures

Below the present invention is described in detail with reference to the accompanying figures, in which the same numbers indicate similar parts. In the figures:

1 and 2 illustrate the selectivity and performance of the catalysts of the present invention.

FIGS. 3A-C illustrate the relative insensitivity of the selectivity and productivity of the catalysts of the present invention to temperature changes along with the change in properties obtained when acetic acid is hydrogenated at 225 ° C. over a catalyst activated at 225 ° C.

On figa-C presents graphs of changes in selectivity, conversion and performance, superimposed on changes in the ratio of platinum to tin in the preferred platinum-tin catalysts of the present invention.

On figa and b illustrates the selectivity of the most preferred catalysts of the present invention on a substrate of silicon dioxide with a highly developed surface, designed to produce ethanol, as well as the high performance achieved when using them.

On figa and b and figa and b illustrates the excellent selectivity obtained at low temperature for the most preferred catalysts of the present invention based on silicon dioxide with a highly developed surface, promoted by calcium metasilicate. It can be recognized that the selectivity for ethanol formation is high.

On Fig, 9 and 10 illustrates the effect of the mass fraction of rhenium on the hydrogenation of acetic acid using the catalyst of the present invention, palladium-rhenium on silicon dioxide.

11 and 12 illustrate the performance of the platinum-cobalt catalyst on silicon dioxide.

DETAILED DESCRIPTION OF THE INVENTION

Despite the fact that market conditions are constantly changing, for large-scale production, the indicators of selectivity, activity, and service life of the catalyst given in the literature for the catalytic hydrogenation of acetic acid to ethanol, usually the economic indicators of the process are unfavorable in order to compete with other methods for producing ethanol. One of the evaluations of the productivity needed to ensure profitability showed that selectivity for ethanol production of more than about 50% is required with a productivity of about 200 g of ethanol per kg of catalyst per hour.

In the following description, all numbers disclosed are approximate values, regardless of whether the words “about” or “approximately” are used in connection with them. They can vary by 1 percent, 2 percent, 5 percent or, sometimes, from 10 to 20 percent. When a numerical range with a lower limit R ^L and an upper limit R ^{U is} disclosed, any number within this range, as well as any sub-range, are specifically indicated. In particular, the following numbers within the range are specifically indicated: R = R ^L + k * (R ^U -R ^L ), where k is a variable varying from 1 percent to 100 percent in increments of 1 percent, that is, k is 1 percent , 2 percent, 3 percent, 4 percent, 5 percent, ..., 50 percent, 51 percent, 52 percent, ..., 95 percent, 96 percent, 97 percent, 98 percent, 99 percent, 100 percent. In addition, any numerical range given by two R numbers, as described above, is also specifically indicated.

1 and 2 illustrate the selectivity and performance of the catalysts of the present invention, graphically representing the increase in selectivity and performance achieved by using these catalysts at different operating temperatures. Namely, at 280 ° C and 296 ° C, the selectivity for ethanol is about 60%. Assessing this fact, it is important to recall that ethyl acetate is also an industrial product of great importance and value for the economy, therefore, even if the main goal is to produce ethanol, any amount of acetic acid converted to ethyl acetate still has value, then like any alkanes formed as by-products, they are usually much less valuable than this raw material. In Fig. 1, the productivity, expressed in grams of ethanol produced per kilogram of catalyst per hour during operation, is presented as a function of time (in hours) and is shown in squares, while the performance for ethyl acetate is shown in circles and the performance for acetaldehyde is shown by diamonds. Essentially, during this experiment, the operating temperature was increased, as shown in the graph, to demonstrate the effect of the operating temperature on productivity and selectivity. 2, the ethanol selectivity, as defined later in this description, is represented by circles as a function of operating time, while the ethyl acetate selectivity, as defined below, is shown in squares, and the acetaldehyde selectivity is shown by diamonds.

FIGS. 3A-C illustrate the relative insensitivity of the selectivity of the catalysts of the present invention to changes in temperature at which the metal precursor is reduced. This characteristic is important from the point of view of economic efficiency, since it is possible to carry out a reaction in a tank that is not specially adapted to maintain the same temperature throughout its length, usually such tanks are called “adiabatic reactors”, since they are poorly adapted to compensate for temperature changes accompanying the reaction process , despite the fact that it is customary to "dilute" the catalyst with quartz chips or other inert particles to slow down the reaction. On figa shows the results of an experiment in which the catalyst was restored at temperatures indicated in ° C, then the hydrogenation reaction between hydrogen and acetic acid was carried out over this catalyst at 250 ° C. The top line shows the selectivity of a particular catalyst with respect to ethanol, while the bottom line shows the selectivity with respect to ethyl acetate. On figv presents the results of this experiment in terms of performance, here the top line corresponds to the performance of ethanol, the bottom line to the performance of ethyl acetate. On figs presents the results of this experiment in relation to conversion (as defined below in this description) as a function of temperature recovery. In addition, acetic acid was also hydrogenated at a temperature of 225 ° C over a catalyst reduced or activated at 225 ° C. FIGS. 3B and 3C also show points reflecting the results of an experiment in which acetic acid was also hydrogenated at 225 ° C. over a catalyst reduced at 225 ° C. It should be noted that hydrogenation over this catalyst at a temperature of 225 ° C is characterized by a reduced selectivity with respect to ethanol and a reduced conversion.

On figa-C presents graphs of changes in selectivity, conversion and productivity, superimposed on changes in the ratio of platinum to tin in the preferred platinum-tin catalysts of the present invention, in comparison with the molar fraction of Pt in SiO ₂ -Pt _x Sn _(1-x) (Σ [Pt] + [Sn] = 1.20 mmol) during the catalytic hydrogenation of acetic acid using 2.5 ml of solid catalyst (14/30 mesh, diluted 1: 1 (vol./vol.) With quartz chips, 14 / 30 mesh); at operating pressure p = 200 psig (14 bar); feed rates of acetic acid, hydrogen and nitrogen diluent 0.09 g / min HOAc; 160 stcm ³ / min N ₂ and 60 stcm ³ / min N ₂ , respectively; however, the total space velocity (GHSV) for 12 hours of the reaction was 6570 h ^-1 . It should be noted that in this experiment, the selectivity for ethanol formation is maximum at a molar ratio of about 1 to 1 for catalysts, the substrate of which is essentially pure silicon dioxide with a highly developed surface. (Throughout the present description (in English), a lowercase “l” is used to designate a liter to avoid ambiguity due to the fact that many font types use the same or even identical characters for the one and lowercase twelfth letters of the Latin alphabet .) In each of FIGS. 4A-4C, Xj (Pt) on the horizontal axis indicates the mass fraction of platinum in the catalyst, varying from zero to unity, while selectivity, conversion and productivity are shown as indicated above; on figa presents the selectivity of the catalyst in relation to the formation of ethanol and ethyl acetate, the peak of selectivity in relation to the formation of ethanol falls on the value of the mass fraction of 50%, where, as shown in figv, the conversion of acetic acid is as maximum as the performance on ethanol, as shown in figs.

On figa and b illustrates the selectivity and performance of the most preferred catalysts of the present invention on a substrate of silicon dioxide with a highly developed surface, designed to produce ethanol, as well as the high performance achieved when using them. In Fig. 5A, the productivity in grams per kilogram of catalyst per hour is given along the vertical axis, while the ethanol production rate is shown in squares, the ethyl acetate production rate is shown in circles, and the acetaldehyde production rate is shown in diamonds. Similarly, in FIG. 5B, selectivity, as defined later in this description, is given along the vertical axis as a function of operating time in hours, measured along the horizontal axis, while, similarly, productivity in relation to the formation of ethanol is shown by squares, productivity in relation to the formation of ethyl acetate shown in circles, performance in relation to the formation of acetaldehyde is shown by diamonds.

On figa and b and figa and b illustrates the selectivity obtained at low temperature using the preferred catalyst of the present invention based on silicon dioxide with a highly developed surface, promoted with calcium metasilicate; they use the same notation as in FIGS. 5A and B. It can be recognized that the selectivity for ethanol formation in this experiment exceeds 90%.

8-12 are discussed in connection with the corresponding examples.

The invention will now be described in detail with reference to numerous embodiments thereof for the purpose of explanation only and by way of illustration. Those skilled in the art will understand that various modifications of specific embodiments of the invention are possible without departing from the spirit and scope of the present invention.

Unless otherwise specified more specifically below, the terminology used in the present description has the usual meaning, "%" and similar terms correspond to mass percent, unless otherwise indicated. As a rule, when the composition of the substrate is described, the percentages of this composition include oxygen, as well as ions or metals connected to it, while when describing the mass of catalytically active metals, the mass of oxygen connected to them is ignored. Thus, in a substrate containing 95% silica and 5% alumina, the reducible composition is based on alumina having a molecular weight formula of 101.94 and silica having a molecular weight of 60.09 by the formula. However, when talking about a catalyst as containing 2% platinum and 3% tin, the mass of any oxygen that can be combined with them is ignored.

"Conversion" is expressed as the molar percentage based on acetic acid in the feed stream.

AcOH conversion (%) mmol AcOH input (feed stream) mmol AcOH output (GC) = one hundred* mmol AcOH input (feed stream)

"Selectivity" is expressed as the molar percentage based on converted acetic acid. For example, if the conversion is 50 mol%, and 50 mol% converted acetic acid was converted to ethanol, meaning that the selectivity for the formation of ethanol is 50%. The selectivity for ethanol formation is calculated based on gas chromatography (GC) data as follows:

Selectivity for the formation of EtOH (%) mmol EtOH GC = one hundred * total mmol C
output (GC) - mmol AcOH output (GC) 2

Without being bound by any theory, it is believed that the conversion of acetic acid to ethanol in accordance with the present invention includes one or more of the following reactions:

Hydrogenation of acetic acid to ethanol.

Hydrogenation of acetic acid to ethyl acetate.

Cracking ethyl acetate to ethylene and acetic acid.

Dehydration of ethanol to ethylene.

Selective catalysts for the hydrogenation of acetic acid to ethanol are catalysts selected from the group consisting of:

(i) catalysts combining a platinum group metal selected from the group consisting of platinum, palladium and mixtures thereof, with tin or rhenium, on a silica support selected from the group consisting of silicon dioxide, calcium metasilicate or silicon dioxide, promoted with calcium metasilicate ;

(ii) catalysts combining palladium and rhenium on a silica support as described above, optionally promoted with a promoter in an amount of 1% to 5%, selected from the group consisting of alkali metals, alkaline earth elements and zinc; however, the promoter is preferably added to the catalytic composition in the form of the corresponding nitrates or acetates, of which, potassium, cesium, calcium, magnesium and zinc are particularly preferred;

(iii) cobalt promoted platinum on a silica support; and

(iv) cobalt promoted palladium on a silica support.

The method of the present invention can be practiced in a variety of configurations using a fixed bed reactor or a fluidized bed reactor, as will be appreciated by those skilled in the art. In many embodiments, an “adiabatic” reactor may be used, that is, with little or no piping inside the reaction zone to supply or remove heat. Alternatively, a shell and tube reactor equipped with a heat transfer medium may be used. In many cases, the reaction zone can be located in a single tank or in a group of tanks with heat exchange between them. It is considered important that acetic acid reduction processes using the catalysts of the present invention can be carried out in adiabatic reactors, since such a reactor configuration usually requires much less capital expenditure than shell-and-tube reactors.

As a support for acetic acid hydrogenation catalysts, various catalyst supports known in the art can be used. Examples of such supports include, but are not limited to, iron oxide, silicon dioxide, alumina, titanium oxide, zirconium oxide, magnesium oxide, calcium silicate, carbon, graphite, and mixtures thereof. In the present invention, it is preferable to use a silica support selected from the group consisting of silica, calcium metasilicate or silica promoted with calcium metasilicate, especially preferably with fumed silica containing SiO ₂ of at least 99.7% if the support is granulated into a mold dense enough for use in fixed-bed reactors. The authors found that highly pure silica with a highly developed surface, especially Saint-Gobain NorPro HSA SS 61138, optionally promoted with calcium metasilicate, unexpectedly turned out to be better than other catalyst supports of the present invention. Preferably, the silica used as the substrate in the present invention has a surface area of at least 100 m ² / g, more preferably at least 150 m ² / g, more preferably at least 200 m ² / g, most preferably about 250 m ² / g. In this description, the term "highly developed silica" is to be understood as meaning silica having a surface area of at least 250 m ² / g. The activity / stability of the silica support can be modified by the introduction of minor amounts of other components, as described herein below. Any suitable particle shape may be used, including granules, extrudates, spheres, dried sprays, rings, pentac rings, trilobal and quadrilobal elements, although cylindrical granules are generally preferred for the present invention.

Effect of catalyst support

Besides the choice of a metal precursor (i.e., halogen, Cl ^- or halogen-free NO ₃ ^- ) and the production conditions resulting from the metal-substrate interaction, strictly depend on the structure and properties of the underlying substrate.

For many Pt-Sn materials on a silicon dioxide substrate, the effects of basic and acid modifiers have been studied. The molar ratio between Pt and Sn for these materials was kept at 1: 1; the total dosage of the metal was also kept constant, unless otherwise indicated. It should be noted that the catalysts obtained on acidic substrates, such as SiO ₂ , SiO ₂ -TiO ₂ , KA160 (i.e., SiO ₂ -Al ₂ O ₃ ) and H-ZSM5, allowed to obtain a high degree of conversion of acetic acid, but a lower selectivity for the formation of ethanol. Interestingly, the H-ZSM5 catalyst, in fact, ensured that diethyl ether, most likely resulting from ethanol dehydration, was obtained as the main product. Both catalysts, based on SiO ₂ -TiO ₂ and КА160 (i.e., SiO ₂ -Al ₂ O ₃ ), provided a high degree of conversion and the same selectivity for the formation of EtOH and EtOAc, with EtOAc being the main product in both cases. It is believed that the presence of Lewis acidity in the underlying catalyst support may be beneficial in increasing the degree of conversion of acetic acid. Although acidity in SiO ₂ -TiO ₂ is mainly due to Lewis acidity, KA160 (silica-alumina) also has strong Bransted acid centers, which can catalyze the formation of EtOAc from acetic acid and EtOH residues. The catalyst based on H-ZSM5 has even stronger Bransted acid zeolite centers, and selectivity depending on the form of the reagents, due to small pores, can also contribute to the acid-catalyzed formation of diethyl ether by ethanol dehydration. Adding a basic modifier to any of the studied substrates led, as a rule, to an increase in selectivity for ethanol formation, accompanied by a significant decrease in the degree of conversion of acetic acid. The highest selectivity for the formation of ethanol, 92%, was recorded for SiO ₂ -CaSiO ₃ (5) -Pt (3) -Sn (1,8), table A, paragraph 2, and even pure TiO ₂ promoted by CaSiO ₃ , provided the formation of ethanol with a selectivity of about 20%. A comparison of SiO ₂ -TiO ₂ and TiO ₂ -CaSiO ₃ suggests that the density of acid (Lewis) centers can also be important, and further optimization of the acid properties of the catalyst substrates can most likely be achieved by carefully varying the main and acid promoters in combination with specific methods of obtaining.

Table a
Generalized data on the activity of the catalyst for various modifiers of the substrate of the catalyst for gas-phase hydrogenation of acetic acid. Reaction conditions : 2.5 ml of solid catalyst (14/30 mesh, diluted 1: 1 (vol./about.) Quartz chips, 14/30 mesh); p = 200 psig (14 bar); 0.09 g / min HOAc; 160 stcm ³ / min H ₂ ; 60 stcm ³ / min N ₂ ; GHSV = 6570 h ^-1 ; reaction time 12 hours No. Catalyst ^one Product selectivity ² % Conversion of SPLAc ³ % ASN EtOH EtOAc one SiO ₂ -Pt _x Sn _1-x ; x = 0.50 - 74 26 73 2 SiO ₂ -CaSiO ₃ (5) -Pt (3) -Sn (1,8) 2 92 6 24 3 SiO ₂ -WO ₃ (10) -Pt (3) -Sn (1,8) - 77 23 17 four SiO ₂ -TiO ₂ (10) -Pt (3) -Sn (1,8) - 47 53 73 5 TiO ₂ -CaSiO ₃ (5) -Pt (3) -Sn (1,8) - 22 78 38 6 KA160-Pt (3) -Sn (1,8) one 47 52 61 7 KA160-CaSiO ₃ (8) -Pt (3) -Sn (1,8) one 84 fifteen 43 8 (H-ZSM-5) -Pt (3) -Sn (1,8) ⁴ - - 44 78 ⁴ 9 SiO ₂ -Re _x Pd _1-x ; x = 0.75 - 56 44 9 10 SiO ₂ -CaSiO ₃ (5) -Re (4,5) -Pd (1) - 83 17 8 ^{1 The} preparation of individual catalysts is described in detail in the present description. The numbers in parentheses indicate the amount of actually present component (metal, metal oxide) in% of the mass.
² Selectivity of product formation (% wt.) Was calculated on the basis of GC analysis after calibration with an authentic sample.
^{3 The} conversion of acetic acid (%) was calculated by the formula: Conversion [HOAc],% = {[HOAc] (fed, mmol / min) -
[HOAc] (outlet, mmol / min) / [HOAc] (feed, mmol / min)} * 100.
⁴ The main product obtained on this catalyst is diethyl ether, EtOEt, with a selectivity of 96%, productivity 2646 g / kg / h.

A significant shift in selectivity towards the formation of ethanol is observed when comparing the promoted catalysts KA160 (SiO ₂ -5% Al ₂ O ₃ ) and KA160-CaSiO ₃ . Although the selectivity for these catalysts was 84%, it was still lower than that recorded for the base material SiO ₂ -CaSiO ₃ , the degree of conversion of acetic acid remained equal to 43%, almost twice what was observed for SiO ₂ -CaSiO ₃ ( 5) -Pt (3) -Sn (1,8), see table A, paragraphs 2, 6 and 7. It is believed that in addition to the properties of the “acid modifier”, CaSiO ₃ exhibits longer stability (albeit at lower degrees conversions). Namely, the SiO ₂ -CaSiO ₃ (5) -Pt (3) -Sn (1,8) catalyst showed a less than 10% decrease in activity over more than 220 hours of reaction under various reaction conditions. Two Re-Pd catalysts prepared on SiO ₂ and SiO ₂ —CaSiO ₃ also had a similar selectivity tendency. Although the conversion rate remained less than 10% for both materials, for the CaSiO _3- promoted material, there was a significant shift in selectivity towards ethanol formation, see Table A, paragraphs 9 and 10. Additional performance information is presented in Table 4.

Thus, without connection with a certain theory, the modification and stabilization of oxide substrates of acetic acid hydrogenation catalysts by introducing non-volatile stabilizer modifiers having either the effect of neutralizing acid centers present on the substrate surface or the effect of thermal stabilization of the surface makes it possible to achieve the necessary increase in selectivity in in relation to the formation of ethanol, lengthening the life of the catalyst, or both. Typically, oxide-based modifiers in their most stable valence state, have lower vapor pressure and, therefore, are most likely non-volatile. Therefore, it is preferable that the hydrogenation catalysts based on Group VIII metals (Fe, Co, Ni, Ru, Rh, Pd, Ir, Pt and Os) or other transition metals (namely Ti, Zn, Cr, Mo and W) on oxide substrates, they contained basic non-volatile stabilizing modifiers either on the surface or in the substrate itself, in the form of oxides and metasilicates of alkaline earth metals, alkali metals, zinc, scandium, yttrium, precursors of these oxides or metasilicates and their mixtures in quantities sufficient to neutralize acidic centers present on the surface of the substrate, imparting resistance to change in shape (mainly due, inter alia, to sintering, grain growth, migration of grain boundaries, migration of defects and dislocations, plastic deformation and / or other thermal changes in the microstructure) at temperatures used in the hydrogenation of acetic acid acids; or both.

The amount of metal deposited on the substrate is not critical in the present invention and can vary from about 0.3 weight percent to about 10 weight percent. Application of the metal from about 0.5 weight percent to about 6 weight percent by weight of the catalyst is particularly preferred. Due to the extremely high cost, platinum group metals are usually used in carefully controlled amounts, often less than 10% of the mass. by weight of the entire catalyst composition. Only 0.25-5% of platinum, together with other catalytically active elements, as described herein, can provide excellent selectivity, durability and activity. Typically, it is preferable to use 0.5-5%, more preferably 1-3% of platinum in the platinum-containing catalysts of the present invention. In the case of platinum-tin catalysts, it is preferable to use 0.10 to 5% tin, more preferably 0.25 to 3% tin, even more preferably 0.5 to 2.5% tin, most preferably a combination of about 3% platinum and approximately 1.5% tin, which quite accurately corresponds to the molar ratio of platinum to tin 1: 1, when the substrate is silicon dioxide with a very developed surface / calcium metasilicate, or a smaller proportional amount, based on the lower mass content of platinum. For this catalyst, it is preferable to use a silica support selected from the group consisting of high purity silica with a highly developed surface, as described above, calcium metasilicate and highly silica, promoted with calcium metasilicate. Thus, it can be understood that the amount of calcium metasilicate can vary over a wide range from 0 to 100% by weight. Since calcium metasilicate has a smaller surface area, it is preferable to include at least about 10% of silica with a highly developed surface from the described supports for this catalyst, more preferably, it is preferable to use approximately 95% of silica with a strongly developed surface as a support, carrier a highly developed surface silica catalyst SS61138 (HSA) from Saint-Gobain NorPro having a surface area of 250 m ² / g; median pore diameter 12 nm; total pore volume 1.0 cm ³ / g, measured by mercury porosimetry, and packing density of about 22 lbs / cubic meter. ft (353 kg / m ³ ).

The catalysts of the present invention are particulate catalysts in the sense that instead of impregnating a reactive primer on a monolithic support, like automotive catalysts and diesel soot traps, the catalysts of the present invention are shaped into particles, sometimes also called balls or granules, which have a different shape, and catalytically active metals are provided in the reaction zone by placing in the reactor a large number of such catalyst particles of a special shape. Common forms include extrudates of arbitrary cross-section, taking the form of a generalized cylinder in the sense that parallel lines are the generating element that defines the surface of the extrudate. Suitable for use are spheres dried by spraying microspheres, rings, pentacles, and multicomponent elements. Usually, the form is chosen empirically based on the subjectively assessed ability to make effective contact between the vapor phase and the catalytic agents.

The most suitable platinum-tin catalyst contains about 3% platinum, 1.5% of the mass. tin, on a silica substrate with a highly developed surface, the surface area of which is about 250 m ² / g, promoted with calcium metasilicate in an amount of about 0.55 to 7.5%. The authors have already reached the service life of the catalyst with this composition in hundreds of hours in a stream at 280 ° C. In many cases, it will be possible to partially replace platinum with palladium in the compositions described above.

A catalyst similar to that described in the previous paragraph, but containing a smaller amount of extremely expensive platinum, promoted with a large amount of cobalt, provides a good initial catalytic activity, but tends to have a shorter service life compared to the platinum-tin catalysts described above. The preference hierarchy for the silica support for this catalyst is substantially the same as for the platinum-tin catalysts. Preferred catalysts of this class include from 0.25 to 5% platinum, more preferably from 0.3 to 3% platinum, most preferably from 0.5 to 1.5% platinum in combination with from about 1% to about 20% cobalt, more preferably about 2% to about 15% cobalt, most preferably about 8% to about 12% cobalt. Even though these catalysts are not as durable as the platinum-tin catalysts described above, in many cases this will be largely offset by the significantly reduced required amount of platinum, the low cost of cobalt compared to the platinum group metals, and excellent initial selectivity. Of course, it is clear that in many cases it is possible to compensate for the lack of activity by properly recirculating the streams or using large reactors, but it is much more difficult to compensate for the low selectivity.

Catalysts based on platinum promoted with rhenium or cobalt provide excellent catalytic activity with slightly lower selectivity, while the loss of selectivity is enhanced at a reaction temperature of more than 280 ° C, leading to the formation of more acetaldehyde, carbon dioxide and even hydrocarbons. Cobalt-containing catalysts typically have slightly higher selectivity than the corresponding rhenium catalysts; but, while both provide unexpectedly long catalytic activity, none of them have such an exceptional catalyst life as the most preferred platinum-tin catalysts on high-purity alumina stabilized and modified with calcium metasilicate. Similarly, silica substrates stabilized and modified by oxides and metasilicates of the elements of group I, group II and zinc described above, as well as their precursors and their mixtures, can serve as a support for this catalyst. Most suitable precursors include acetates and nitrates of zinc, alkali metals and alkaline earth metals, which optionally can be introduced into the silica substrate in an amount of about 1-5% based on the weight of the metal, excluding acetate and / or nitrate groups.

In other embodiments of the present invention, the catalysts described above can be modified by introducing modifiers selected from the group consisting of redox modifiers; acidity modifiers and mixtures thereof, in a silica substrate and, thereby, a shift in relative selectivity between ethanol, ethyl acetate and acetaldehyde. Suitable redox modifiers include WO ₃ , MoO ₃ , Fe ₂ O ₃ and Cr ₂ O ₃ , while acidity modifiers include TiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ and Al ₂ O ₃ . By thoughtfully introducing these modifiers into the silica substrate, it is possible to adjust the activity of the catalyst in such a way as to obtain a more desirable distribution of the relative amounts of catalytic hydrogenation products, in order to match the changes in market conditions and the need for different products. Typically, these materials are included in the silica support in an amount lying in the range of about 1 to 50% by weight.

Metal impregnation may be carried out using any of the methods known in the art. Typically, before impregnation, the substrate material is dried at 120 ° C and shaped into particles with a size distribution in the range of about 0.2 to 0.4 mm. Optionally, the substrate may be compressed, ground, and sieved to obtain a predetermined size distribution. Any of the known methods for shaping the substrate materials with a predetermined size distribution can be applied. In a preferred catalyst preparation method, a component corresponding to a platinum group metal, such as a suitable compound and / or platinum group metal complex, can be used to obtain the distribution of the catalytically active component on a substrate, for example, on the particles of the substrate. Water-soluble compounds or water-dispersible compounds or metal complexes of the platinum group can be used to impregnate or deposit catalytically active metal compounds on substrate particles. The component corresponding to the platinum group metal decomposes upon heating and / or under vacuum. In some cases, the final removal of the liquid may not occur until the use of the catalyst has been started and the high temperature occurring during operation has been created. Usually, both in terms of economic parameters and environmental impact, aqueous solutions of soluble compounds of platinum group metals are preferred. Suitable compounds are, for example, platinum chloride, amine solubilized platinum hydroxide, palladium nitrate or palladium chloride, sodium palladium chloride, sodium platinum chloride and the like, although it is preferable to use halogens when the target product is ethanol. In the calcining step, or at least in the initial phase of the use of the catalyst, such compounds are converted to the catalytically active form of the platinum group metal or its catalytically active oxide. However, platinum group metal precursors that are chloride-free are generally preferred, as it has been found by the authors that catalysts prepared from Pt (NH ₃ ) ₄ (NO ₄ ) ₂ exhibit increased selectivity for ethanol formation.

In such cases, when the catalysts of the present invention are bimetallic, it is generally considered that one metal acts as a promoter and the other metal is a base metal. For example, in the case of a platinum-tin catalyst, platinum can be considered as the base metal for the preparation of the hydrogenation catalysts of the present invention, while tin should be considered as a promoting metal. However, it should be noted that sometimes such a separation can be misleading, especially when the selectivity of the platinum-tin catalyst with respect to the formation of ethanol, the target product, approaches zero both in the absence of tin and in the absence of platinum. For convenience, it is preferable to call the metal or metals of the platinum group the main catalyst, and other metals - promoters. This should not be taken as a reflection of the underlying mechanism of catalytic activity.

Bimetallic catalysts are often impregnated in two stages. First, the promoter metal is added, then the main metal. Each stage of impregnation is accompanied by drying and firing. Bimetallic catalysts can also be prepared by simultaneous impregnation. In the case of promoted bimetallic catalysts, as described above, sequential impregnation can be used, starting with the addition of a “promoter” metal followed by a second impregnation step comprising simultaneously impregnating with two “base” metals, that is, Pt and Sn. For example, PtSn / CaSiO ₃ on SiO ₂ can be prepared by first impregnating CaSiO ₃ on SiO ₂ and then simultaneously impregnating with diluted impurities platinum chloride, solubilized in amine, platinum hydroxide, palladium nitrate or palladium chloride, sodium palladium chloride, platinum sodium chloride Pt (NH ₃ ) ₄ (NO ₄ ) ₂ and the like. Similarly, each stage of impregnation is accompanied by drying and firing. In most cases, the impregnation can be carried out using solutions of metal nitrate. However, various other soluble salts can also be used which, when fired, emit metal ions. Examples of other impregnable metal salts include metallic acids, for example, a solution of rhenic acid, metal oxalates, and the like. In those cases where it is necessary to obtain substantially pure ethanol, it is usually preferable to avoid the use of halogenated metal precursors of the platinum group, using precursors based on nitrogenous amine and / or nitrate instead.

The reaction can be carried out in a vapor state under a wide range of conditions. Preferably, the reaction is carried out in the vapor phase. Reaction temperatures may be employed, for example, in the range of from about 125 ° C to 350 ° C, typically from about 200 ° C to 325 ° C, preferably from about 225 ° C to 300 ° C, most preferably from about 250 ° C to 300 ° C. Pressure is usually not a determining factor for this reaction; pressures below atmospheric, atmospheric, or above atmospheric may be applied. In most cases, however, the pressure of this reaction lies in the range of about 1 to 30 atm. abs. In another aspect of the method of the present invention, the hydrogenation is usually carried out at a pressure sufficient only to overcome the pressure drop across the catalyst bed at a selected full hourly space velocity (GHSV), although there are no obstacles to using a higher pressure, that at a space velocity of from 5000 h ^-1 to 6500 h ^-1 , which is quite acceptable for the catalysts of the present invention, there may be a significant pressure drop on the catalyst bed in the reactor.

Although the reaction consumes two moles of hydrogen per mole of acetic acid and one mole of ethanol is formed, the real molar ratio of hydrogen to acetic acid in the feed stream can vary over a wide range, for example, from about 100: 1 to 1: 100. Preferably, however, this ratio is in the range of about 1:20 to 1: 2. Most preferably, the molar ratio of hydrogen to acetic acid is about 5: 1.

The starting materials used according to the method of the present invention can come from any suitable source, including natural gas, oil, coal, biomass, etc. It is well known that acetic acid is produced by carbonylation of methanol, oxidation of acetaldehyde, oxidation of ethylene, oxidative fermentation, anaerobic fermentation, etc. As oil and natural gas tend to fluctuate at a higher or lower cost, methods for producing acetic acid and intermediates such as methanol and carbon monoxide from alternative carbon sources are of growing interest. In particular, when oil is more expensive than natural gas, it may be advantageous to produce acetic acid from synthesis gas obtained from any suitable carbon source. In US patent 6232352, in the name of Vidalin, the description of which is incorporated into this description by reference, for example, the idea of a method for upgrading a methanol production plant for the production of acetic acid is described. With the modernization of the methanol plant, the significant investment associated with the formation of CO in the new plant for the production of acetic acid is significantly reduced or substantially eliminated. All or part of the synthesis gas is removed from the methanol synthesis loop and fed to a separator for the recovery of CO and hydrogen, which are then used to produce acetic acid. In addition to acetic acid, the method can also be used to produce hydrogen, which is used according to the present invention.

US patent RE 35377, to Steinberg et al., Also incorporated herein by reference, describes a method for producing methanol by converting carbonaceous material such as oil, coal, natural gas, and biomass. This method involves the hydrogasification of solid and / or liquid carbon materials to produce a process gas, which is subjected to steam pyrolysis with the addition of natural gas to produce synthesis gas. The synthesis gas is converted to methanol, which can be carbonylated to acetic acid. By this method, hydrogen is also obtained, which can be used according to the present invention, as noted above. See also US Pat. No. 5,821,111 to Grady et al. For a method for converting biomass waste by gasification to synthesis gas, and US 6,685,754 to Kindig et al., The disclosures of which are incorporated herein by reference.

Acetic acid can be converted to steam at the reaction temperature and then fed with undiluted hydrogen or diluted with a relatively inert carrier gas such as nitrogen, argon, helium, carbon dioxide, etc.

Alternatively, the acetic acid in the vapor phase can be taken directly as a crude product from the vaporization tank of a methanol carbonylation unit belonging to the class described in US Pat. No. 6,557,078 to Scates et al., The disclosure of which is incorporated herein by reference. The crude vaporous product can be fed directly to the reaction zones of the present invention without the need for condensation of acetic acid and light fractions or removal of water, thereby reducing the overall processing cost.

Contact time or residence time also varies widely depending on such variables as the amount of acetic acid, catalyst, reactor, temperature and pressure. Typically, the contact time is from fractions of a second to more than a few hours when a different catalyst system is used than the fixed bed, and the preferred contact time, at least for reactions in the vapor phase, is from about 0.5 to 100 seconds.

Typically, the catalyst is used in a fixed-bed reactor, for example, in the form of an elongated tube or tubular chamber, where the reactants, usually in the vapor phase, pass over the catalyst or through the catalyst. Optionally, other reactors, such as fluidized bed or fluidized bed reactors, may be used. In some cases, hydrogenation catalysts can be used in combination with an inert material, such as glass wool, to control the pressure drop of the reactant stream on the catalyst bed and the contact time of the reactant compounds with the catalyst particles.

The following examples describe the preparation of various catalysts used in the method of the present invention. In the sections "Cooking" and "Examples", where (in the text in English) the lowercase "l" is used, this is done in order to avoid duality and distinguish between the Latin lowercase "l", the number "1" and the uppercase or lowercase the letter “l”, which is characteristic of many fonts and / or typesets, and since the meaning of the wording follows from the commonly used, it should be understood that this means “liters” despite the absence of any international sanctions in this regard.

Catalyst Preparation (General)

Before use, the catalyst supports were dried at 120 ° C. overnight in circulating air. All commercially available substrates (i.e., SiO ₂ , ZrO ₂ ) were used in the form of a 14/30 mesh or in the original form (granules 1/16 inch or 1/8 inch (1.6-3.2 mm), if not specified etc. Powdered materials (ie, CaSiO ₃ ) were granulated, ground and sieved after the addition of metals, The next section describes in detail the preparation of the individual catalysts.

Preparation of Catalyst A

Preparation of 0.5% of the mass. platinum and 5% of the mass. tin with high-purity silica with a small surface area

Powdered and sieved silica with a highly developed surface NPSG SS61138 (100 g) with a uniform particle size distribution of about 0.2 mm was dried at 120 ° C in an oven in a nitrogen atmosphere overnight, then cooled to room temperature. To it was added a solution of platinum nitrate (Chempur) (0.82 g) in distilled water (8 ml) and a solution of tin oxalate (Alfa Aesar) (8.7 g) in diluted nitric acid (1N, 43.5 ml). The resulting suspension was dried in an oven while gradually heating to 110 ° C (> 2 hours, 10 ° C / min). The impregnated catalyst mixture was then calcined at 500 ° C. (6 hours, 1 ° C./min).

Catalyst Preparation B

Preparation of 1% of the mass. platinum and 1% of the mass. tin silica with a highly developed surface

Essentially, the procedure for preparing catalyst A was repeated, except that a solution of platinum nitrate (Chempur) (1.64 g) in distilled water (16 ml) and a solution of tin oxalate (Alfa Aesar) (1.74 g) in diluted nitrogen were used. acid (1N, 8.5 ml).

Catalyst Preparation C

Preparation of 1% of the mass. platinum and 1% of the mass. tin on calcium metasilicate

Essentially, the procedure for preparing catalyst B was repeated, except that a solution of platinum nitrate (Chempur) (1.64 g) in distilled water (16 ml) and a solution of tin oxalate (Alfa Aesar) (1.74 g) in diluted nitrogen were used. acid (1N, 8.5 ml), and using calcium metasilicate as a catalyst support.

Catalyst Preparation D

Preparation of 0.5% of the mass. platinum, 0.5% of the mass. tin and 0.2% of the mass. highly developed cobalt on silica

Powdered and sieved silica with a highly developed surface (100 g) with a uniform particle size distribution of about 0.2 mm was dried at 120 ° C in an oven in a nitrogen atmosphere overnight, then cooled to room temperature. To it was added a solution of platinum nitrate (Chempur) (0.82 g) in distilled water (8 ml) and a solution of tin oxalate (Alfa Aesar) (0.87 g) in diluted nitric acid (1N, 4.5 ml). The resulting suspension was dried in an oven while gradually heating to 110 ° C (> 2 hours, 10 ° C / min). The impregnated catalyst mixture was then calcined at 500 ° C. (6 hours, 1 ° C./min). To the calcined and cooled material was added a solution of cobalt hexahydrate nitrate (0.99 g) in distilled water (2 ml). The resulting suspension was dried in an oven while gradually heating to 110 ° C (> 2 hours, 10 ° C / min). The impregnated catalyst mixture was then calcined at 500 ° C. (6 hours, 1 ° C./min).

Catalyst Preparation E

Preparation of 0.5% of the mass. tin silica with a small surface area

Powdered and sieved silica with a small surface area (100 g) with a uniform particle size distribution of about 0.2 mm was dried at 120 ° C in an oven in a nitrogen atmosphere overnight, then cooled to room temperature. To it was added a solution of tin oxalate (Alfa Aesar) (1.74 g) in dilute nitric acid (1N, 8.5 ml). The resulting suspension was dried in an oven while gradually heating to 110 ° C (> 2 hours, 10 ° C / min). The impregnated catalyst mixture was then calcined at 500 ° C. (6 hours, 1 ° C./min).

Catalyst Preparation F

Preparation of 2% of the mass. platinum and 2% of the mass. tin with high purity silica with a highly developed surface

Powdered and sieved silica with a highly developed surface NPSG SS61138 (100 g) with a uniform particle size distribution of about 0.2 mm was dried at 120 ° C in an oven in a circulating air atmosphere overnight, then cooled to room temperature. To it was added a solution of nitrate hexahydrate (Chempur). The resulting suspension was dried in an oven while gradually heating to 110 ° C (> 2 hours, 10 ° C / min), and then calcined. To the resulting material was added a solution of platinum nitrate (Chempur) in distilled water and a solution of tin oxalate (Alfa Aesar) in dilute nitric acid. The resulting suspension was dried in an oven while gradually heating to 110 ° C (> 2 hours, 10 ° C / min). The impregnated catalyst mixture was then calcined at 500 ° C. (6 hours, 1 ° C./min).

Catalyst Preparation G

Preparation of 1% of the mass. platinum and 1% of the mass. tin silica with a highly developed surface promoted with 5% ZnO

Essentially, the preparation of catalyst F was repeated, except that: a zinc hexahydrate nitrate solution was added to the highly developed surface silica described in the preparation of catalyst F. The resulting suspension was dried in an oven while gradually heating to 110 ° C (> 2 hours, 10 ° C / min), then subjected to firing. After that, a solution of platinum nitrate (Chempur) in distilled water and a solution of tin oxalate (Alfa Aesar) (1.74 g) in diluted nitric acid (1N, 8.5 ml) were added to zinc-promoted silica with a highly developed surface.

Catalyst Preparation H

Preparation of 1% of the mass. platinum and 1% of the mass. Zn on silica with a highly developed surface promoted with 5% SnO ₂

Essentially, the procedure for preparing catalyst G was repeated, except that: a tin acetate solution (Sn (OAc) ₂ ) was added to highly developed silica instead of zinc hexahydrate; and a solution of platinum nitrate, Pt (NH ₃ ) ₄ (NO ₃ ) ₂ (Aldrich), in distilled water and a solution of tin oxalate (Alfa Aesar) in dilute nitric acid.

Catalyst Preparation I

Cooking 1.5% of the mass. platinum and 0.5% of the mass. tin on calcium metasilicate

Essentially, the preparation of Catalyst C was repeated using a solution of platinum nitrate (Chempur) in distilled water and a solution of tin oxalate (Alfa Aesar) in dilute nitric acid.

Catalyst Preparation J

Cooking 1.5% of the mass. platinum and 10% of the mass. highly developed cobalt on silica

In essence, the procedure for preparing catalyst H was repeated using a solution of platinum nitrate (Chempur) in distilled water and, instead of tin oxalate, a solution of cobalt (II) hexahydrate nitrate (1.74 g). The compositions of the prepared catalysts, as well as brief information about the compositions of other catalysts prepared in a similar way and tested, are shown in table 1.

Preparation of catalysts KO

SiO ₂ -Pt _x Sn _1-x  (0 <x <1)

Five materials were prepared by changing the molar fraction of Pt, but keeping the total amount of metal (Pt + Sn) equal to 1.20 mmol. The following describes the preparation of the catalyst K, SiO ₂ —Pt _0.5 Sn _0.5 (i.e., x = 0.5; equimolar ratio of metals). In the remaining cases (i.e., x = 0, 0.25, 0.75, and 1.00; preparation of the L, M, N, and O catalysts, respectively), the catalysts were prepared in a similar manner using the appropriate amounts of Pt (NH ₃ ) metal precursors ₄ (NO ₃ ) ₂ and Sn (OAc) ₂ . The catalysts were first prepared by adding Sn (OAc) ₂ (tin acetate, Sn (OAc) ₂ from Aldrich) in a test tube containing 6.75 ml diluted 1: 1 glacial acetic acid (Fisher). The mixture was stirred for 15 minutes at room temperature, then 0.2323 g (0.60 mmol) of solid Pt (NH ₃ ) ₄ (NO ₃ ) ₂ (Aldrich) was added thereto. The mixture was stirred for another 15 minutes at room temperature, then it was added dropwise to 5.0 g of a dry SiO ₂ support (high purity silica catalyst support HSA SS # 61138, SA (surface area) = 250 m ² / g; SZ # 61152, SA = 156 m ² / g; Saint-Gobain NorPro) in a 100 ml round-bottom flask. The metal solution was continuously stirred until the entire Pt / Sn mixture was added to the SiO ₂ substrate, and the flask was rotated after each addition of the metal solution. Upon completion of the addition of the metal solution, the flask with the impregnated catalyst was left at room temperature for two hours. Then the flask was attached to a rotary evaporator (bath temperature 80 ° C) and vacuumized to dryness, slowly rotating the flask. Then the material was additionally dried overnight at 120 ° C, then calcined using the following temperature program: 25 ° C → 160 ° C, heating rate 5.0 deg / min; keeping for 2.0 hours; 160 ° C → 500 ° C, heating rate 2.0 deg / min; aging for 4 hours. Yield: 5.2 g of a dark gray material.

Catalyst Preparation P

SiO ₂ -CaSiO ₃ (5) -Pt (3) -Sn (1,8)

The material was obtained by first adding CaSiO ₃ (Aldrich) to the SiO ₂ substrate and then adding Pt / Sn, as described above. First, an aqueous CaSiO ₃ solution (≤200 mesh) was prepared by adding 0.52 g of solid material in 13 ml of deionized H ₂ O, followed by 1.0 ml of colloidal SiO ₂ (15% by weight solution, NALCO). The suspension was stirred for 2 hours at room temperature, then added to 10.0 g of a SiO ₂ support (14/30 mesh) using the initial humidity technique. After standing for 2 hours, the material was evaporated to dryness, then dried at 120 ° C. overnight in circulating air and calcined at 500 ° C. for 6 hours. Then all the material SiO ₂ - CaSiO _{3 was} used for impregnation with a mixture of Pt / Sn metals, using 0.6711 g (1.73 mmol) Pt (NH ₃ ) ₄ (NO ₃ ) ₂ and 0.4104 g (1.73 mmol) Sn (OAc) ₂ , following the procedure described above for materials SiO ₂ -Pt _x Sn _1-x . Yield: 11.21 g of a dark gray material.

Catalyst Preparation Q

CaSiO ₃ -Pt (1) -Sn (1)

40 ml of 1.0 M HNO _{3 was} added to a 100 ml round bottom flask with a Teflon-coated magnetic stirrer, then 0.2025 g (0.52 mmol) of solid Pt (NH ₃ ) ₄ (NO ₃ ) _{2 was} added. The resulting Pt complex was dissolved with stirring, and then 0.2025 g (0.87 mmol) of solid Sn (OAc) _{2 was} added. Then, 10.0 g of CaSiO ₃ (≤200 mesh) was added with stirring; the mixture was then heated to 80 ° C. and stirred at this temperature for two hours. Then the suspension was evacuated to dryness using a rotary evaporator (bath temperature 80 ° C), the solid material was transferred to a porcelain cup and dried overnight at 120 ° C in circulating air. After firing (25 ° C → 160 ° C, heating rate 5.0 deg / min; holding for 2.0 hours; 160 ° C → 500 ° C, heating rate 2.0 deg / min; holding for 4 hours ) the material was pressed, granulated under pressure, applying a force of 40,000 pounds (18144 kg) to the pressed particles for 15 minutes, grinded and sieved to 14/30 mesh. Yield: 9.98 g of a brownish material.

Catalyst Preparation R

SiO ₂ -TiO ₂ (10) -Pt (3) -Sn (1,8)

A substrate of modified TiO ₂ silica was prepared as follows. A solution of 4.15 g (14.6 mmol) of Ti {OCH (CH ₃ ) ₂ } ₄ in 2-propanol (14 ml) was added dropwise to 10 g of a SiO ₂ support (1/16 inch extrudates (1.6 mm) ) in a 100 ml round-bottom flask. The flask was left for two hours at room temperature, then it was evacuated to dryness using a rotary evaporator (bath temperature 80 ° C). Then, 20 ml of deionized water was slowly added to the flask, and the material was left for 15 minutes. Then the water / 2-propanol mixture was removed by filtration and the addition of water was repeated two more times. The resulting material was dried at 120 ° C. overnight in circulating air, then calcined at 500 ° C. for 6 hours. Then, all the SiO ₂ —TiO ₂ material was used for impregnation with Pt / Sn metals using 0.6711 g (1.73 mmol) Pt (NH ₃ ) ₄ (NO ₃ ) ₂ and 0.4104 g (1.73 mmol) Sn (OAc) ₂ , following the procedure described above for SiO ₂ -Pt _x Sn _1-x materials. Yield: 11.98 g of 1/16 inch (1.6 mm) dark gray extrudates.

Catalyst Preparation S

SiO ₂ -Wo ₃ (10) -Pt (3) -Sn (1,8)

A substrate of modified WO ₃ silica was prepared as follows. A solution of 1.24 g (0.42 mmol) (NH ₄ ) ₆ H ₂ W ₁₂ O ₄₀ · nH ₂ O, (AMT) in deionized water (14 ml) was added dropwise to 10.0 g of a SiO ₂ NPSGSS 61138 substrate (SA = 250 m ² / g, 1/16 inch (1.6 mm) extrudates) in a 100 ml round bottom flask. The flask was left for two hours at room temperature, then it was evacuated to dryness using a rotary evaporator (bath temperature 80 ° C). The resulting material was dried at 120 ° C. overnight in circulating air, then calcined at 500 ° C. for 6 hours. Then, all (light yellow) SiO ₂ —WO ₃ material was used to impregnate with Pt / Sn metals using 0.6711 g (1.73 mmol) Pt (NH ₃ ) ₄ (NO ₃ ) ₂ and 0.4104 g (1 , 73 mmol) Sn (OAc) ₂ , following the procedure described above for materials SiO ₂ -Pt _x Sn _1-x . Yield: 12.10 g 1/16 inch dark gray extrudates (1.6 mm).

Catalyst Preparation T

(H-ZSM-5) -Pt (3) -Sn (1,8)

The material was obtained by impregnating a suspension of H-ZSM-5 (obtained from NH ₄ -ZSM-5 by calcination at 550 ° C for 8 hours in an atmosphere of air). An aqueous solution of 0.6711 g (1.73 mmol) of Pt (NH ₃ ) ₄ (NO ₃ ) ₂ and 0.4104 g (1.73 mmol) of Sn (OAc) _{2 was} obtained by adding these components to 40 ml of diluted 1: 1 acetic acid in a 100 ml round-bottom flask and stirring the resulting mixture for 15 minutes at room temperature. Then, 10.0 g of solid finely divided H-ZSM-5 was added to the resulting solution with stirring, and the mixture was stirred for another two hours at room temperature. The flask was evacuated to dryness using a rotary evaporator (bath temperature 80 ° C), the resulting material was dried at 120 ° C overnight in circulating air. After firing (250 ° C → 160 ° C, heating rate 5.0 deg / min; holding for 2.0 hours; 160 ° C → 500 ° C, heating rate 2.0 deg / min; holding for 4 hours ) the material was pressed, granulated, ground and sieved to 14/30 mesh. Yield: 9.55 g of grayish material.

Catalyst Preparation U

SiO ₂ -Re _x Pd _1-x  (0 <x <1)

Five materials were prepared by changing the molar fraction of Re, but keeping the total amount of metal (Re + Pd) equal to 1.20 mmol. The following describes the preparation of SiO ₂ -Re _0.5 Pd _0.5 (i.e., x = 0.5; equimolar metal ratio). In the remaining cases (i.e., x = 0, 0.25, 0.75 and 1.00), the preparation was carried out in a similar manner using the appropriate amounts of the precursors of the metals NH ₄ ReO ₄ and Pd (NO ₃ ) ₂ . Metal solutions were first prepared by adding to the test tube containing 6.75 ml of deionized water, NH ₄ ReO ₄ (0.1609 g, 0.60 mmol). The mixture was stirred for 15 minutes at room temperature, then 0.1154 g (0.60 mmol) of solid Pd (NO ₃ ) _{2 was} added thereto. The mixture was stirred for another 15 minutes at room temperature, then it was added dropwise to 5.0 g of a dry SiO ₂ support (14/30 mesh) in a 100 ml round bottom flask. After complete addition of the metal solution, the flask with the impregnated catalyst was left at room temperature for two hours. Then the flask was attached to a rotary evaporator (bath temperature 80 ° C) and evacuated to dryness. All other manipulations (drying, firing) were carried out as described above for materials SiO ₂ -Pt _x Sn _1-x , see above. Yield: 5.1 g of brown material.

Catalyst Preparation V

SiO ₂ -CaSiO ₃ (5) -Re (4,5) -Pd (1)

A substrate of modified SiO ₂ - CaSiO ₃ (5) was prepared as described above for SiO ₂ - CaSiO ₃ (5) -Pt (3) -Sn (1,8), see above. Then, a Re / Pd catalyst was prepared by impregnating SiO ₂ - CaSiO ₃ (5) (1/16 inch (1.6 mm) extrudates) with an aqueous solution containing NH ₄ ReO ₄ and Pd (NO ₃ ) ₂ . Metal solutions were first prepared by adding to a test tube containing 12.0 ml of deionized water, NH ₄ ReO ₄ (0.7237 g, 2.70 mmol). The mixture was stirred for 15 minutes at room temperature, then 0.1756 g (0.76 mmol) of solid Pd (NO ₃ ) _{2 was} added thereto. The mixture was stirred for another 15 minutes at room temperature, then it was added dropwise to 10.0 g of a dry SiO ₂ - (0.05) CaSiO ₃ support in a 100 ml round-bottom flask. After complete addition of the metal solution, the flask with the impregnated catalyst was left at room temperature for two hours. All other manipulations (drying, firing) were carried out as described above for SiO ₂ -Re _x Pd _1-x materials, see above. Yield: 10.9 g of brown material.

Catalyst Preparation W

CaSiO ₃ -Re (5) -Pd (2,5)

The material was obtained by impregnating a suspension of CaSiO ₃ (powder, ≤200 mesh). An aqueous solution of 0.6169 g (2.30 mmol) of NH ₄ ReO ₄ and 0.5847 g (2.53 mmol) of Pd (NO ₃ ) _{2 was} prepared by adding these components to 40 ml of deionized water in a 100 ml round-bottom flask and stirring the resulting mixture for 15 minutes at room temperature. Then, 10.0 g of solid finely ground CaSiO _{3 was} added to the resulting solution with stirring, and the mixture was stirred for another two hours at room temperature. The flask was evacuated to dryness using a rotary evaporator (bath temperature 80 ° C), the resulting material was dried at 120 ° C overnight in circulating air. All other manipulations (drying, firing) were carried out as described above for materials SiO ₂ -Pt _x Sn _1-x , see above. The resulting material was pressed using a press that exerts a force of 40,000 pounds (18,144 kg) for 15 minutes, milled and sieved to 14/30 mesh. Yield: 10.65 g of a brownish material.

Catalyst Preparation X

SiO ₂ -Co (10) -Pt (1)

The material was obtained by impregnating HSA SiO ₂ (silicon oxide with a highly developed surface) (14/30 mesh) with an aqueous solution containing Co (NO ₃ ) ₂ · 6H ₂ O and Pt (NH ₃ ) ₄ (NO ₃ ) ₂ . A metal solution was first prepared by adding to a test tube containing 12.0 ml of deionized water, Co (NO ₃ ) ₂ · 6H ₂ O (5.56 g, 19.1 mmol). The mixture was stirred for 15 minutes at room temperature, then 0.2255 g (0.58 mmol) of solid Pt (NH ₃ ) ₄ (NO ₃ ) _{2 was} added. The mixture was stirred for another 15 minutes at room temperature, then it was added dropwise to 10.0 g of a dry SiO ₂ support (14/30 mesh) in a 100 ml round bottom flask. After complete addition of the metal solution, the flask with the impregnated catalyst was left at room temperature for two hours. All other manipulations (drying, firing) were carried out as described above for materials SiO ₂ -Pt _x Sn _1-x , see above. Yield: 11.35 g of black material.

Catalyst Preparation Y

CaSiO ₃ -Co (10) -Pt (1)

The material was obtained by impregnating a suspension of CaSiO ₃ (powder, ≤200 mesh). An aqueous solution of 5.56 g (19.1 mmol) of Co (NO ₃ ) ₂ · 6H ₂ O and 0.2255 g (0.58 mmol) of Pt (NH ₃ ) ₄ (NO ₃ ) _{2 was} prepared by adding these components to 40 ml of deionized water in a 100 ml round-bottom flask and stirring the resulting mixture for 15 minutes at room temperature. Then, 10.0 g of solid finely ground CaSiO _{3 was} added to the resulting solution with stirring. The mixture was then heated to 65 ° C and stirred at this temperature for another two hours. Then the flask was evacuated to dryness using a rotary evaporator (bath temperature 80 ° C), the resulting material was dried at 120 ° C overnight in circulating air. All other manipulations (drying, firing) were carried out as described above for the material SiO ₂ —Co (10) —Pt (1), see above. The resulting material was pressed, milled and sieved to 14/30 mesh. Yield: 10.65 g of black material.

Catalyst Preparation Z

Zro ₂ -Co (10) -Pt (1)

The material was obtained by impregnating ZrO ₂ (SZ61152, Saint-Gobain NorPro, 14/30 mesh) with an aqueous solution containing Co (NO ₃ ) ₂ · 6H ₂ O and Pt (NH ₃ ) ₄ (NO ₃ ) ₂ . Metal solutions were first prepared by adding to a test tube containing 5.0 ml of deionized water, Co (NO ₃ ) ₂ · 6H ₂ O (5.56 g, 19.1 mmol). The mixture was stirred for 15 minutes at room temperature, then 0.2255 g (0.58 mmol) of solid Pt (NH ₃ ) ₄ (NO ₃ ) _{2 was} added. The mixture was stirred for another 15 minutes at room temperature, then it was added dropwise to 10.0 g of a dry ZrO ₂ support (14/30 mesh) in a 100 ml round bottom flask. After complete addition of the metal solution, the flask with the impregnated catalyst was left at room temperature for two hours. All other manipulations (drying, firing) were carried out as described above for SiO ₂ —Co (10) —Pt (1) materials, see above. Yield: 11.35 g of black material.

Catalyst Preparation AA

SiO ₂ -CaSiO ₃ (2.5) -Pt (1.5) -Sn (0.9)

The material was obtained as described above for SiO ₂ - CaSiO ₃ (5) -Pt (3) -Sn (1,8) using 0.26 g of CaSiO ₃ , 0.5 ml of colloidal SiO ₂ (15% wt. Solution, NALCO), 0.3355 g (0.86 mmol) Pt (NH ₃ ) ₄ (NO ₃ ) ₂ and 0.2052 g (0.86 mmol) Sn (OAc) ₂ . Yield: 10.90 g of a dark gray material.

Preparation of catalyst BB

TiO ₂ -CaSiO ₃ (5) -Pt (3) -Sn (1,8)

The material was first prepared by adding CaSiO ₃ to a TiO ₂ substrate (Anatas, 14/30 mesh) and then adding Pt / Sn, as described above. First, an aqueous suspension of CaSiO ₃ (≤200 mesh) was prepared by adding 0.52 g of solid material in 7.0 ml of deionized H ₂ O, followed by adding 1.0 ml of colloidal SiO ₂ (15% w / w solution, NALCO). The suspension was stirred for 2 hours at room temperature, then 10.0 g of a TiO ₂ support (14/30 mesh) was added using the initial humidity technique. After standing for 2 hours, the material was evaporated to dryness, then dried at 120 ° C. overnight in circulating air and calcined at 500 ° C. for 6 hours. Then, all the TiO ₂ - CaSiO ₃ material was used for impregnation with a Pt / Sn metal mixture using 0.6711 g (1.73 mmol) Pt (NH ₃ ) ₄ (NO ₃ ) ₂ and 0.4104 g (1.73 mmol) Sn (OAc) ₂ , following the procedure described above for materials SiO ₂ -Pt _x Sn _1-x . Yield: 11.5 g of light gray material.

CC catalyst preparation

KA160-Pt (3) -Sn (1,8)

The material was obtained by impregnating a KA160 substrate (SiO ₂ - (0.05) Al ₂ O ₃ , Sud Chemie, 14/30 mesh) using the initial moisture technique as described above for SiO ₂ -Pt _x Sn _1-x materials, cm below. Metal solutions were first prepared by adding to a test tube containing 4.75 ml of diluted 1: 1 glacial acetic acid, Sn (OAc) ₂ (0.2040 g, 0.86 mmol). The mixture was stirred for 15 minutes at room temperature, then 0.3350 g (0.86 mmol) of solid Pt (NH ₃ ) ₄ (NO ₃ ) _{2 was} added. The mixture was stirred for another 15 minutes at room temperature, then it was added dropwise to 5.0 g of KA160 support (14/30 mesh) in a 100 ml round-bottom flask. All other manipulations, drying and calcination was carried out as described above for SiO ₂ —Pt _x Sn _1-x materials, see above. Yield: 5.23 g of brown material.

DD catalyst preparation

KA160-CaSiO ₃ (8) -Pt (3) -Sn (1,8)

The material was first prepared by adding CaSiO ₃ to the KA160 substrate and then adding Pt / Sn, as described above for KA160-Pt (3) -Sn (1,8). First, an aqueous suspension of CaSiO ₃ (≤200 mesh) was prepared by adding 0.42 g of solid material in 3.85 ml of deionized H ₂ O, followed by the addition of 0.8 ml of colloidal SiO ₂ (15% by weight solution, NALCO). The suspension was stirred for 2 hours at room temperature, then 5.0 g of KA160 substrate (14/30 mesh) was added using the initial moisture technique. After standing for 2 hours, the material was evaporated to dryness, then dried at 120 ° C. overnight in circulating air and calcined at 500 ° C. for 6 hours. Then all the KA160- CaSiO ₃ material was used for impregnation with a mixture of Pt / Sn metals using 0.3350 g (0.86 mmol) Pt (NH ₃ ) ₄ (NO ₃ ) ₂ and 0.2040 g (0.86 mmol) Sn (OAc) ₂ , following the procedure described above for SiO ₂ -Pt _x Sn _1-x materials. Yield: 5.19 g of tan material.

Table 1
Systematized Catalyst Data Prepared Platinum Group Metal Promoter Other Substrate Example A 0.5% of the mass. Pt 5% of the mass. Sn - HP LSA SiO ₂ one B 1% of the mass. Pt 1% of the mass. Sn - HP LSA SiO ₂ 2 C 1% of the mass. Pt 1% of the mass. Sn - CaSiO ₂ four D 0.5% of the mass. Pt 0.5% of the mass. Sn 0.2% of the mass. With HP LSA SiO ₂ - E - 0.5% of the mass. Sn - HP LSA SiO ₂ Wed one F 2% of the mass. Pt 2% of the mass. Sn - HSA SiO ₂ G 1% of the mass. Pt 1% of the mass. Sn 5% of the mass. Zno HSA SiO ₂ four H 1% of the mass. Pt 1% of the mass. Zn 5SnO ₂ HSA SiO ₂ four I 1.5% of the mass. Pt 0.5% of the mass. Sn - CaSiO ₂ four J 1% of the mass. Pt - 10% of the mass. With HSA SiO ₂ four K SiO ₂ -Pt _x Sn _(1-x) (Σ [Pt] + [Sn] = 1.20 mmol) X = 0.5 - HSA SiO ₂ L SiO ₂ -Pt _x Sn _(1-x) (Σ [Pt] + [Sn] = 1.20 mmol) X = 0 - HSA SiO ₂ M SiO ₂ -Pt _x Sn _(1-x) (Σ [Pt] + [Sn] = 1.20 mmol) X = 0.75 - HSA SiO ₂ N SiO ₂ -Pt _x Sn _(1-x) (Σ [Pt] + [Sn] = 1.20 mmol) X = 0.25 - HSA SiO ₂ O SiO ₂ -Pt _x Sn _(1-x) (Σ [Pt] + [Sn] = 1.20 mmol) X = 1 HSA SiO ₂ P 3% of the mass. Pt 1.8% of the mass. Sn 5% of the mass. CaSiO ₃ HSA SiO ₂ Q 1% of the mass. Pt 1% of the mass. Sn CaSiO ₃ R 3% of the mass. Pt 1.8% of the mass. Sn 10% of the mass. TiO ₂ HSA SiO ₂ ? S 3% of the mass. Pt 1.8% of the mass. Sn Wo ₃ HSA SiO ₂ T 3% of the mass. Pt 1.8% of the mass. Sn H-ZSM-5 U SiO ₂ -Re _x Pd _(1-x) (Σ [Re] + [Pd] = 1.20 mmol) X = 0.5 HSA SiO ₂ V SiO ₂ -Re _x Pd _(1-x) (Σ [Re] + [Pd] = 1.20 mmol) X = 0 HSA SiO ₂ W SiO ₂ -Re _x Pd _(1-x) (Σ [Re] + [Pd] = 1.20 mmol) X = 0.25 HSA SiO ₂

X SiO ₂ -Re _x Pd _(1-x) (Σ [Re] + [Pd] = 1.20 mmol) X = 0.75 HSA SiO ₂ Y SiO ₂ -Re _x Pd _(1-x) (Σ [Re] + [Pd] = 1.20 mmol) X = 1 HSA SiO ₂ Z 1 mol% Pd 4.5 mol% Re 5% of the mass. CaSiO ₃ HSA SiO ₂ ? AA 1.5% Pt 0.9% Sn 2.5% CaSiO ₃ SiO ₂ BB 3% Pt 1.8% Sn 5% CaSiO ₃ TiO ₂ CC 3% Pt 1.8% Sn KA160 DD 3% Pt 1.8% Sn 8% CaSiO ₃ KA160 AAA 2.5% of the mass. Pd 5% of the mass. Re CaSiO ₃ BBB 1% Pt 10% of the mass. With HSA SiO ₂ CCC 1% Pt 10% of the mass. With CaSiO ₃ DDD 1% Pt 10% of the mass. With ZrO ₂

Gas chromatographic (GC) analysis of products

Product analysis was carried out by gas chromatography online. A three-channel small-sized gas chromatograph equipped with a flame ionization detector (PID) and two heat conductivity detectors (DT) was used to analyze reagents and products.

The front channel, equipped with a PID and a CP-Sil 5 column (20 m) + WaxFFap (5 m), was used to quantify: acetaldehyde; ethanol; acetone; methyl acetate; vinyl acetate; ethyl acetate; acetic acid; ethylene glycol diacetate; ethylene glycol; ethylidene diacetate; paraldehyde.

A middle channel equipped with an AP and a Porabond Q column was used to quantify: CO ₂ ; ethylene; ethane.

The back channel, equipped with a TD and a Molsieve 5A column, was used to quantify: helium; hydrogen; nitrogen; methane; carbon monoxide.

Prior to the reaction, the retention time of the various components was determined by introducing the individual components, and the GC devices were calibrated using either a calibration gas of known composition or liquid solutions of known composition. This made it possible to determine response factors for various components.

Example 1

In a tubular reactor made of stainless steel with an internal diameter of 30 mm suitable for heating to a controlled temperature, 50 ml of the catalyst was prepared, prepared as described above in the Preparation of Catalyst C. The length of the combined catalyst layer after loading was approximately 70 mm.

The feed liquid consisted essentially of acetic acid. The supplied reaction liquid was evaporated and introduced into the reactor together with hydrogen and helium as a carrier gas at an average total hourly gas space velocity ( GHSV) of 2500 h ^-1 , a temperature of 250 ° C and a pressure of 100 psig (0.69 MPa). The feed stream contained acetic acid at a molar percentage of about 6.1% to about 7.3% and hydrogen at a molar percentage of about 54.3% to about 61.5%. Part of the vaporous stream leaving the reactor was directed through a gas chromatograph to analyze the composition of this stream. The selectivity for ethanol formation was 93.4% with an acetic acid conversion of 85%.

Used catalyst was 1% of the mass. platinum and 1% of the mass. tin on silica prepared in accordance with the procedure described for the preparation of catalyst A.

Example 2

Used catalyst was 1% of the mass. platinum and 1% of the mass. tin on calcium silicate prepared in accordance with the procedure described for the preparation of catalyst C.

The procedure described for example 1 was essentially repeated with a GHSV feed stream of vaporous acetic acid and hydrogen of 2500 h ^-1 , a temperature of 250 ° C. and a pressure of 22 bar (2.2 MPa). Part of the vaporous stream leaving the reactor was directed through a gas chromatograph to analyze the composition of this stream. The conversion of acetic acid exceeded 70%, the selectivity for the formation of ethanol was 99%.

Comparative Example 1

Used catalyst was 1% of the mass. tin on high-purity silicon dioxide with a small surface area, prepared in accordance with the procedure described for the preparation of catalyst E.

The procedure described for example 1 was essentially repeated with a GHSV feed stream of vaporous acetic acid and hydrogen of 2500 h ^-1 , a temperature of 250 ° C. and a pressure of 22 bar (2.2 MPa). Part of the vaporous stream leaving the reactor was directed through a gas chromatograph to analyze the composition of this stream. The conversion of acetic acid was less than 10%, the selectivity for the formation of ethanol was less than 1%.

Example 3

The procedure of Example 2 was repeated using several catalysts at the temperature indicated in Table 2, which also shows the percentage of carbon monoxide (CO), acetaldehyde (AcH) and ethane in the products, as well as selectivity and performance for ethyl acetate, ethanol; and percent conversion of acetic acid (HOAc) (MCD p.4). In all cases, the molar ratio of H ₂ to acetic acid was maintained at 5: 1. For convenience, the results obtained in examples 1 and 2 and in comparative example 1 are also included in table 2. Typically, when ethanol is desired as the target product, it is desirable that the selectivity for ethanol is more than 80% or so; and the ethyl acetate selectivity was less than 5%, preferably less than 3%.

table 2 Prepared Catalyst The temperature in the reactor, ° C With AsN,% Ethane,% EtOAc,% EtOH,% EtOAc g / kg / h EtOH g / kg / h SPLA, g / kg / h TO SiO ₂ -Pt _x Sn _1-x ; x = 0 250 - - - - - - - - L SiO ₂ -Pt _x Sn _1-x ; x = 0.25 250 - - - 41 59 473 683 28 M SiO ₂ -Pt _x Sn _1-x ; x = 0.50 250 - - - 26 74 788 2217 73 N SiO ₂ -Pt _x Sn _1-x ; x = 0.75 250 - - - 72 28 482 186 17 O SiO ₂ -Pt _x Sn _1-x ; x = 1.00 250 - - - one hundred - 125 - 3 U SiO ₂ -Re _x Pd _1-x ; x = 0 - - - 62 38 126 77 5 V SiO ₂ -Re _x Pd _1-x ; x = 0.25 - - - 80 twenty 305 75 9 W SiO ₂ -Re _x Pd _1-x ; x = 0.50 - - - 77 23 344 102 eleven X SiO ₂ -Re _x Pd _1-x ; x = 0.75 - - - 44 56 170 218 9 Y SiO ₂ -Re _x Pd _1-x ; x = 1.00 - - - one hundred - 52 0 one S SiO ₂ -TiO ₂ (10) -Pt (3) -Sn (1,8) - - - 53 47 1648 1454 73 T (H-ZSM-5) -Pt (3) -Sn (1,8) ⁷ - - - four - 107 - 78 ⁷ U SiO ₂ -Re _x Pd _1-x ; x = 0 - - - 62 38 126 77 5 V SiO ₂ -Re _x Pd _1-x ; x = 0.25 - - - 80 twenty 305 75 9

W SiO ₂ -Re _x Pd _1-x ; x = 0.50 - - - 77 23 344 102 eleven X SiO ₂ -Re _x Pd _1-x ; x = 0.75 - - - 44 56 170 218 9 Y SiO ₂ -Re _x Pd _1-x ; x = 1.00 - - - one hundred - 52 0 one CC KA160-Pt (3) -Sn (1,8) 250 3 - fifty 47 1036 946 61 DD KA160-CaSiO ₃ (8) -Pt (3) -Sn (1,8) 250 3 - 13 84 213 1151 43 P SiO ₂ -CaSiO ₃ (5) -Pt (3) -Sn (1,8) 250 - 2 - 6 92 62 926 24 ^{1 The} preparation of individual catalysts is described in detail in the present description. The numbers in parentheses indicate the amount of actually present component (metal, metal oxide) in% of the mass.
² Selectivity of product formation (% wt.) Was calculated on the basis of GC analysis after calibration with an authentic sample.
^{3 The} conversion of acetic acid (%) is calculated by the formula:
Conversion of [HOAc],% = {[HOAc] (feed, mmol / min) - [HOAc] (feed, mmol / min) / [HOAc] (feed, mmol / min)} * 100.
⁴ STY (yield in grams per hour per 1 kg of catalyst) is calculated by the formula: [Product] (g) / [catalyst] (kg) / h.
⁵ Additionally, a certain amount of CH ₄ and CO (5% wt. Each) was also noted.
^{6 The} data in the first row were obtained after 2 hours of reaction time. The second line shows the data obtained after 8 hours. In addition, some CH ₄ and CO were also noted: 2 hours; CH ₄ 4% of the mass .; WITH 4% of the mass .; 8 h; CH ₄ 10% of the mass .; WITH 9% of the mass.
⁷ The main product obtained on this catalyst is diethyl ether, EtOEt, the selectivity was 96%, and the productivity was 2646 g / kg / h.

Example 4

Vaporous acetic acid and hydrogen were passed over a hydrogenation catalyst of the present invention containing 2% by weight. Pt and 2% of the mass. Sn on silica with a highly developed surface (NPSG SS61138), the surface area of which was approximately 250 m ² / g, with a ratio of hydrogen to acetic acid of approximately 150 stcm ³ / min H ₂ : 0.09 g / min HOAc, at moreover, hydrogen was diluted at about 60 stcm ³ / min N ₂ at a space velocity of about 6570 h ^-1 and a pressure of 200 psig (1.4 MPa). The temperature was increased after about 50 hours, 70 hours and 90 hours, as shown in FIGS. 1 and 2, where the productivity in grams of these products (ethanol, acetaldehyde and ethyl acetate) per kilogram of catalyst per hour is shown in FIG. 1, and the selectivity of the catalyst in with respect to the formation of various products is shown in figure 2, while the top line indicates the performance or selectivity for ethyl acetate, the middle line refers to ethanol, the bottom line to acetaldehyde. Especially significant, it is believed, is that the performance and selectivity for acetaldehyde was small. These data are summarized in the summary table below.

Data list

225 ° C 250 ° C 280 ° C 296 ° C Conversion of NOAc,%: 11.15 26.49 36.65 33.77 Performance in relation to EtOH, g / kg / h: 187.65 380.59 517.62 434.67 Selectivity for EtOH,% mass .: 41.96 35.83 35.67 33.07 Performance in relation to EtOAc, g / kg / h: 244.04 638.20 882.55 835.50 Selectivity for EtOAc,% wt .: 57.08 62.79 62.36 63.56

Example 5

The methodology shown for example 1, essentially repeated using a catalyst containing 2% of the mass. Pt; 2% of the mass. Sn on a substrate consisting of silica granules with a highly developed surface SS61138 from Saint-Gobain NorPro, with an average total GHSV of 2500 h ^{-1 of the} supplied stream of vaporous acetic acid, hydrogen and helium, at the temperature indicated in table 2 and a pressure of 100 psig (0.69 MPa). The resulting feed stream contained acetic acid at a molar percentage of about 7.3%, and hydrogen at a molar percentage of about 54.3%. Part of the vaporous stream leaving the reactor was directed through a gas chromatograph to analyze the composition of the stream. The results are presented in table 3.

Table 3
Catalyst stability
2% of the mass. Pt / 2% of the mass. Sn - catalyst “F”? on a HSA SiO substrate ₂  reaction temperature 225 ° C-296 ° C; total working time 115 h 225 ° C 250 ° C 280 ° C 296 ° C Conversion of NOAc,% 11.15 26.49 36.65 33.77 Performance in relation to EtOH, g / kg / h 187.65 380.59 517.62 434.67 Selectivity for EtOH,% wt. 41.96 35.83 35.67 33.07 Performance in relation to EtOAc, g / kg / h 244.04 638.20 8082.55 835.50 Selectivity for EtOAc,% wt. 57.08 62.79 62.36 63.56

The results of example 5 are summarized in figure 3, illustrating that the relative insensitivity of the catalyst to temperature changes makes this catalyst suitable for use in the so-called adiabatic reactor, in which the temperature in the catalyst bed can vary significantly due to the low and non-uniform intensity of heat removal from the reactor.

Example 6

The effect of the molar ratio [Sn] / [Pt] in SiO ₂ -Pt _x Sn _(1-x) catalysts was studied (i) by changing the molar fraction of Pt with constant metal loading ([Pt] + [Sn] = 1.20 mmol) and (ii) as a function of recovery temperature. A distinct maximum at a molar fraction of Pt 0.5 (ie [Sn] / [Pt] = 1.0) was observed both for the conversion of acetic acid and selectivity for ethanol formation. The selectivity for the formation of ethyl acetate changes dramatically at [Sn] / [Pt] = 1.0 in favor of ethanol. At a molar fraction of Pt of either 25% or 75%, the formation of ethyl acetate as the main product is observed. The presence of Pt and Sn in an equimolar ratio is preferable from the point of view of increasing both the conversion of acetic acid and the selectivity for the formation of ethanol, cf. with figa-C.

Vaporous acetic acid (0.09 g / min HOAc) and hydrogen (160 stcm ³ / min H ₂ ) were passed over a hydrogenation catalyst of the present invention containing Pt and Sn on highly developed silica with a surface area of approximately 250 m ² / g, at a temperature of 250 ° C; GHSV = 6570 h ^-1 ; reaction time 12 hours. In this example 6, the amount of metal (Pt + Sn) was kept constant, the mass fraction of platinum was varied from 0 to 1. FIGS. 4A-C illustrate selectivity, activity, and performance for each catalyst. Based on this example, it becomes clear that the maximum selectivity, activity and productivity occurs when the mass fraction of platinum is approximately 0.5, i.e. the amount of platinum by weight is substantially equal to the amount of tin in the catalyst.

Example 7

Vaporous acetic acid and hydrogen were passed over the hydrogenation catalyst of the present invention containing 3% by weight. Pt, 1.5% of the mass. Sn and 5% of the mass. CaSiO ₃ as a promoter on high-purity silica with a highly developed surface, the surface area of which was approximately 250 m ² / g, with a molar ratio of hydrogen to acetic acid of about 5: 1, at a temperature of about 225 ° C. 5A and 5B illustrate the selectivity and performance of the catalysts as a function of the duration of the operation at the initial length of time of the catalyst. From the results of this example, presented in figa and 6B, it becomes clear that it is possible to achieve selective activity of more than 90% and productivity of more than 500 g of ethanol per kilogram of catalyst per hour.

Example 8

The procedure of example 8 was repeated (the same catalyst) at a temperature of about 250 ° C. On figa and 7B illustrates the selectivity and performance of the catalysts as a function of the duration of work at the initial period of time of operation of the catalyst. From the results of this example, presented in figa and 7B, it becomes clear that it is still possible to achieve selective activity of more than 90%, but with a productivity of more than 800 g of ethanol per kilogram of catalyst per hour at this temperature.

Example 9

To study the sensitivity to the temperature used to reduce the platinum and tin bimetallic precursors to catalytically active forms, the effect of the reduction temperature was analyzed by activating the optimized Pt / Sn SiO ₂ - (Pt _0.5 Sn _0.5 ) catalyst, see below, during independent experiments at temperatures from 225 to 500 ° C. In four experiments, the material was activated at 280, 350, 425 and 500 ° C in a stream of hydrogen for 4 hours, then used to restore acetic acid at a reaction temperature of 250 ° C. (The activation of the catalyst was carried out using a 10 mol% mixture of H ₂ / N ₂ (275 st. Cm ³ / min) at atmospheric pressure using the following temperature program: RT → reduction temperature (225-500 ° С), heating rate 2 deg / min; holding for 4.0 hours; then cooling (or heating, if necessary) to 250 ° C to restore HOAc). In addition, the properties of the material activated at 225 ° C were studied at the temperature of the hydrogenation reaction of HOAc 225 and 250 ° C. There was no significant change in selectivity for the formation of ethanol and ethyl acetate over the entire temperature range, including for the catalyst activated at 225 ° C, for reaction temperatures of both 225 and 250 ° C. Interestingly, a significant increase in conversion (and productivity) was observed for catalysts activated at lower, 225 and 280 ° C, reduction temperatures. The decrease in conversion at higher reduction temperatures can be explained by sintering of metal particles. (See FIGS. 7A and 7B). Since no change in selectivity was noted, it was assumed that the composition of the metal particles (i.e., the PtSn alloy) remained unchanged. The results of this example are illustrated in FIGS. 3A-C.

In the course of these examples, many other products were discovered including acetaldehyde, ethanol, ethyl acetate, ethane, carbon monoxide, carbon dioxide, methane, isopropanol, acetone and water.

Example 10

We evaluated the catalytic characteristics of various catalysts during the catalytic hydrogenation of acetic acid using 2.5 ml of solid catalyst from the catalysts shown in Table 4. In each case, the catalyst particles were 14/30 mesh in size and diluted 1: 1 v / v . 14/30 mesh quartz chips. During each experiment, the operating pressure was 200 psig (14 bar, 1.4 MPa) at an acetic acid feed rate of 0.09 g / min; hydrogen 120 stcm ³ / min; nitrogen 60 stcm ³ / min and a total hourly space velocity of 6570 h ^-1 for 24 hours of operation time (TOS). The results are shown in table 4.

Table 4
The activity of various metal catalysts on a substrate during the catalytic hydrogenation of HOAc
Reaction conditions : 2.5 ml of solid catalyst (14/30 mesh, diluted 1: 1 (vol./about. Quartz crumb size 14/30 mesh); p = 200 psig (14 bar, 1.4 MPa); 0, 09 g / min HOAc; 120 st.sm ³ / min H ₂ ; 60 st.s cm ³ / min N ₂ ; GHSV = 6570 h ^-1 ; 24 h TOS No. Catalyst ^one Temp. ° C Selectivity with respect to product formation,% ³ Productivity, g / kg / h Conversion of SPLAc ^four % With ASN Ethane EtOAc EtOH EtOAc EtOH + CuO-MnO ₂ (10) -Al ₂ O ₃ (34) 275 31 71 71 165 58 2 (SA_250-SiO ₂ ) -Pt (2.0) -Sn (2.0) 275 - 5 - 57 38 286 194 81 3 (SA_160-SiO ₂ ) -Re (5.0) -Pd (2.5) 248 31 four 8 6 51 fourteen 126 twenty four (SA_250-SiO ₂ ) -Re (5.0) -Pd (2.5) 225 - eleven - 43 46 52 55 10 5 (SA_160-SiO ₂ ) -Co (10.0) -Pt (1.0) 275 - - - 17 82 31 154 13 6 (SA_250-SiO ₂ ) -Co (10.0) -Pt (1.0) 275 four 5 2 6 79 41 534 fifty 7 (SA_250-SiO ₂ -ZnO) -Pt (1,0) -Sn (1,0) 275 - 3 - 21 76 84 116 22 8 (SA_250-SiO ₂ -ZnO) -Pt (1,0) -Zn (1,0) 275 - 7 - 44 48 93 one hundred 13 9 CaSiO ₃ -Pt (1,0) -Sn (1,0) 275 - four - 17 79 56 261 22 10 (SA_250-SiO ₂ -MgSiO ₃ (5) -Pt (1,0) -Sn (1,0) 250 - 2 - 10 88 35 192 22 eleven CaSiO ₃ -Pt (1,5) -Sn (0,5) 275 - one - eleven 87 12 94 8 12 CaSiO ₃ —Co (10.0) -Pt (1.0) 275 - 5 - 7 87 eighteen 224 24 13 CaSiO ₃ —Co (10.0) -Pt (1.0) -Sn (1.0) 275 four 2 2 60 thirty 188 93 26 fourteen CaSiO ₃ -Re (5.0) -Pd (2.5) 225 5 2 3 5 79 16 259 29th fifteen CaSiO ₃ -Pt (1,0) -Zn (1,0) 275 - 3 - 56 41 58 eleven 7 16 C-Pt (2.0) -Sn (1.0) 275 - - - 43 57 66 88 12 17 CuO (12) -ZnO (62) -Al ₂ O ₃ (25) 225 - - - - one hundred 6 - one ¹ Numbers in parentheses indicate the amount of actually present component in% of the mass. Unless otherwise specified, all materials were tested in situ in a hydrogen atmosphere before testing the catalytic properties.
² T-4489 obtained from Sűd Chemie and used in the obtained condition. Reaction conditions : 5.0 ml of solid catalyst (14/30 mesh, diluted 1: 1 (vol./about. Quartz crumb size 14/30 mesh);

p = 200 psig (14 bar, 1.4 MPa); 0.038 g / min HOAc; 120 stcm ³ / min H ₂ ; 80 stcm ³ / min N ₂ ; GHSV = 2676 h ^-1 ; 24 hours TOS.
³ Product analysis performed by GC analysis after calibration with an authentic sample.
^{4 The} conversion of HOAc (%) was calculated by the formula: {[HOAc] _{t = 0} - [HOAc] _t / [HOAc] ₀ } * 100%.

Example 11

Catalyst Stability: SiO ₂ —CaSiO ₃ (5) —Pt (3) —Sn (1.8). The characteristics of the catalyst and the initial stability of SiO ₂ -CaSiO ₃ (5) -Pt (3) -Sn (1,8) were studied at a constant temperature (260 ° C) for 100 hours of reaction time. During these 100 hours of total reaction time, only small changes in the characteristics of the catalyst and selectivity were noted. The only by-product was acetaldehyde, its concentration (~ 3% wt.) During the experiment remained basically unchanged. On figa and 5B summarized data on the performance and selectivity of this catalyst. The effect of the reaction temperature on product selectivity was studied in a separate experiment over a total reaction time of 125 hours, see above.

Example 12

Productivity and selectivity of 3% Pt: 1.5% Sn on high-purity SiO ₂ with a highly developed surface stabilized with 5% CaSiO ₃ during the hydrogenation of acetic acid was studied during the experiment for 15 hours at 225 ° C using a continuous reaction system with a fixed a catalyst bed for the production of mainly acetaldehyde, ethanol, ethyl acetate by means of hydrogenation and esterification reactions in the usual range of operating conditions, using 2.5 ml of solid catalyst (14/30 mesh, diluted 1: 1 (v / v silica cr with a size of 14/30 mesh); at a pressure of 200 psig (1.4 MPa); feed rates of 0.09 g / min HOAc; 160 st.sm ³ / min N ₂ ; 60 st.sm ³ / min N ₂ ; GHSV = 6570 h ^-1 . The results are displayed in figa and 6B.

Example 13

The performance and selectivity of catalysts containing Re and Pd on SiO ₂ , in which the molar ratio of Re _x Pd _{(1-x) was} changed from catalyst to catalyst, was investigated by changing the molar fraction of Re with constant loading of metal ([Pt] + [Sn] = 1.20 mmol) using 2.5 ml of solid catalyst (14/30 mesh, diluted 1: 1 (v / v with 14/30 mesh quartz chips); at 200 psig (14 bar, 1.4 MPa) ); supplying 0.09 g / min of acetic acid; together with 160 stcm ³ / min of hydrogen; and 60 stcm ³ / min of N ₂ as a diluent; at a temperature of 250 ° C; GHSV = 6570 h ^-1 ; or 12 hours of reaction time I. Although the maximum conversion of acetic acid was recorded with a molar fraction of Re of approximately 0.6, ethanol becomes the main product only with a molar fraction of Re of approximately 0.78. With this molar ratio of Re to Pd (that is, “Re ₇ Pd ₂ ”) selectivity with respect to ethyl acetate, it changes slightly in favor of ethanol. It is important that, as shown for the Pd / Sn series above, the presence of two metals in a certain ratio is a key structural requirement in terms of selectivity for a particular product, that is, a shift in selectivity and in the direction of formation of ethanol we occur at [Re] / [Re + Pd] = 0,78, Wed. Figures 8, 9 and 10, presented in the same format as Figures 4A-C, except that X _i (Re) means the mass fraction of rhenium in the catalyst. However, in contrast to Pt / Sn materials, the maximum conversion of acetic acid and the selectivity for ethanol formation for these materials do not coincide, and favorable selectivity for the formation of ethanol is observed only at low HOAc conversion. Consequently, maximum productivity is observed for ethyl acetate, and not for ethanol, cf. with Fig. 8. In addition, the formation of hydrocarbons (methane and ethane; 5.3 and 2.4 wt.%, Respectively) was observed using the CaSiO ₃ -Re (5) -Pd (2,5) catalyst with an acetic acid conversion of about 30% and a temperature the reaction is only 225 ° C. Although a higher conversion of acetic acid can most likely be achieved by increasing the reaction temperature, the amount of hydrocarbons will probably also increase, thereby limiting the overall efficiency of the Re / Pd catalyst system.

Example 14

Initial screening of the catalyst using a platinum (1%) - cobalt catalyst (Co loading of 10% by mass) on a silica substrate allows high conversion of acetic acid and about 80% ethanol formation selectivity. See Figs. 11 and 12 for selectivity and activity as defined above, wherein the results for ethanol are shown in squares, the results for ethyl acetate are shown in circles, the results for acetaldehyde are shown in diamonds, and the results for ethane are shown in triangles. However, it is believed that the catalyst decomposes, since the selectivity for acetic acid decreases from about 80% to 42% in nine hours of the reaction time. In addition, significant changes in productivity are also observed, and a decrease in selectivity for the formation of ethanol is accompanied by an increase in selectivity for the formation of ethyl acetate and acetaldehyde. Similar results were obtained for 10% cobalt on silica.

Example 15

Vaporous acetic acid (0.09 g / min HOAc) and hydrogen (160 stcm ³ / min H ₂ ; 60 stcm ³ / min N ₂ ) at a pressure of 200 psig (1.4 MPa) were passed over the hydrogenation catalyst of the present inventions containing 3% of the mass. Pt and 1.8% of the mass. Sn on a substrate containing a molecular sieve ZSM-5 in hydrogen form at a temperature of 250 ° C; GHSV = 6570 h ^-1 ; reaction time 12 hours. Diethyl ether was obtained at a selectivity of 96% and a productivity of 2646 g / kg / h, together with 4% ethyl acetate, with 78% acetic acid remaining unreacted.

Example 16

Vaporous acetic acid (0.09 g / min HOAc) and hydrogen (160 stcm ³ / min H ₂ ; 60 stcm ³ / min N ₂ ) at a pressure of 200 psig (1.4 MPa) were passed over the hydrogenation catalyst of the present inventions containing 2% of the mass. Pt and 1% of the mass. Sn on a substrate containing graphite with a highly developed surface at a temperature of 275 ° C; GHSV = 6570 h ^-1 ; reaction time 12 hours. The selectivity for the formation of ethyl acetate was 43%, the selectivity for the formation of ethanol was 57%, the performance for ethyl acetate was 66 g / kg / h, the performance for ethanol was 88 g / kg / h, the conversion of acetic acid - 12%.

Although the present invention has been described in detail, it will be apparent to those skilled in the art that various modifications are possible without departing from the spirit and scope of the present invention. Taking into account the preceding description, relevant information and reference materials discussed above in the sections "Background" and "Detailed description of the invention" and are fully incorporated into the present description by reference, further explanation by examples seems unnecessary. In addition, it should be understood that aspects of the present invention and parts of various variants of its implementation and various distinguishing features listed below and / or in the attached claims, can be combined or replaced, either in whole or in part. In addition, it will be apparent to those skilled in the art that the foregoing description is given by way of example only and is not intended to limit the invention.

Thus, according to the present invention, new methods and catalysts for producing hydrogenated products based on acetic acid are provided.

Embodiment No. 1, for example, is a method for producing ethanol by reducing acetic acid, comprising passing a gaseous stream containing hydrogen and acetic acid in the vapor phase, with a molar ratio of hydrogen to acetic acid of at least about 4: 1, at a temperature from about 225 ° C to 300 ° C over a hydrogenation catalyst containing platinum and tin dispersed on a silica substrate, where the amount and oxidation state of platinum and tin, as well as the ratio of platinum to tin and silica th substrate is selected, make up and adjusted so that the: (i) at least 80% of the converted acetic acid was converted to ethanol; (ii) less than 4% of acetic acid is converted to compounds other than compounds selected from the group consisting of ethanol, acetaldehyde, ethyl acetate, ethylene and mixtures thereof; (iii) the activity of the catalyst decreased by less than 10%, under the influence of a vaporous mixture of acetic acid and hydrogen at a molar ratio of 10: 1 at a pressure of 2 atm, a temperature of 275 ° C and GHSV 2500 h ^-1 for a period of 168 hours.

Embodiment No. 2 is a method of Embodiment No. 1, wherein the hydrogenation catalyst consists essentially of platinum and tin dispersed on a silica substrate, and the silica substrate is a modified silica substrate, wherein the modified silica substrate contains an effective amount of a substrate modifier selected from the group consisting of: (i) alkaline earth metal oxides, (ii) alkali metal oxides, (iii) alkaline earth metal metasilicates, (iv) alkali metal metasilicates, (v) zinc oxide, (vi) zinc metasilicate and (vii) precursors of any of (i) to (vi), and mixtures of any of (i) to (vii).

Embodiment No. 3 is a method of Embodiment No. 2, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment 4 is a method of Embodiment 2, wherein (a) platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; and (b) tin is present in an amount of at least 0.5 to 10%.

Embodiment No. 5 is a method of Embodiment No. 3, wherein the molar ratio of platinum to tin is from 4: 5 to 5: 4.

Embodiment No. 6 is a method of Embodiment No. 2 wherein the substrate modifier is selected from the group consisting of metasilicates of sodium, potassium, magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment No. 7 is the method of Embodiment No. 5, wherein (a) platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; and (b) tin is present in an amount of at least 0.5 to 10%.

Embodiment No. 8 is a method of Embodiment No. 6, wherein the molar ratio of platinum to tin is from 4: 5 to 5: 4.

Embodiment No. 9 is a method of Embodiment No. 2, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

An implementation option No. 10 is a method of an implementation option No. 9, in which (a) platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; and (b) tin is present in an amount of at least 0.5 to 10%.

Embodiment No. 11 is a method of Embodiment No. 10, wherein the molar ratio of platinum to tin is from 4: 5 to 5: 4.

Embodiment No. 12 is a method of Embodiment No. 2, wherein the substrate modifier is selected from the group consisting of metasilicates of magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

An implementation option No. 13 is a method of an implementation option No. 12, in which (a) platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; and (b) tin is present in an amount of at least 0.5 to 10%.

Embodiment No. 14 is a method of Embodiment No. 12, wherein the molar ratio of platinum to tin is from 4: 5 to 5: 4.

Embodiment No. 15 is a method of Embodiment No. 2, wherein the substrate modifier is selected from the group consisting of calcium metasilicate, calcium metasilicate precursors and mixtures of calcium metasilicate, and its precursors.

Embodiment No. 16 is a method of Embodiment No. 15, wherein (a) platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; and (b) tin is present in an amount of at least 0.5 to 10%.

Embodiment No. 17 is a method of embodiment No. 16, wherein the molar ratio of platinum to tin is from 4: 5 to 5: 4.

Embodiment No. 18 is a method of Embodiment No. 2, wherein (a) platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; and (b) tin is present in an amount of at least 0.5 to 10%.

Embodiment No. 19 is a method of Embodiment No. 16, wherein the molar ratio of platinum to tin is from 4: 5 to 5: 4.

Embodiment No. 20 is a method of Embodiment No. 18, wherein the surface area of the substrate is at least about 100 m ² / g.

Embodiment No. 21 is a method of Embodiment No. 20, wherein the molar ratio of tin to platinum group metal is from about 1: 2 to about 2: 1.

Embodiment No. 22 is a method of Embodiment No. 20, wherein the molar ratio of tin to platinum is from about 2: 3 to about 3: 2.

Embodiment No. 23 is a method of Embodiment No. 20, wherein the molar ratio of tin to platinum is from about 5: 4 to about 4: 5.

Embodiment No. 24 is a method of Embodiment No. 2, wherein the surface area of the substrate is at least about 150 m ² / g.

Option exercise No. 25 is the method of embodiment No. 24, in which (a) platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; and (b) tin is present in an amount of at least 0.5 to 5%.

An implementation option No. 26 is a method of an implementation option No. 24, in which the substrate contains at least about 1% to about 10% of the mass. calcium silicate.

Embodiment No. 27 is a method of embodiment No. 24, wherein the molar ratio of tin to platinum is from about 1: 2 to about 2: 1.

Embodiment No. 28 is a method of Embodiment No. 24, wherein the molar ratio of tin to platinum is from about 2: 3 to about 3: 2.

Embodiment No. 29 is a method of embodiment No. 24, wherein the mass ratio of tin to platinum is from about 5: 4 to about 4: 5.

Embodiment No. 30 is a method of Embodiment No. 2, wherein the surface area of the substrate is at least about 200 m ² / g.

Embodiment No. 31 is a method of Embodiment No. 30 wherein the molar ratio of tin to platinum is from about 2: 3 to about 3: 2.

Embodiment 32 is a method of Embodiment 30, wherein the molar ratio of tin to platinum is from about 5: 4 to about 4: 5.

Embodiment No. 33 is a method of Embodiment No. 30 wherein the molar ratio of tin to platinum is from about 9:10 to about 10: 9.

Embodiment No. 34 is a method of Embodiment No. 33, wherein the surface area of the modified silica substrate is at least about 250 m ² / g.

Embodiment No. 35 is a method of Embodiment No. 2, carried out at a temperature of from about 250 ° C to 300 ° C, in which (a) the surface area of the modified silica substrate is at least about 250 m ² / g; (b) platinum is present in the hydrogenation catalyst in an amount of at least about 0.75% by weight .; (c) the molar ratio of tin to platinum is from about 5: 4 to about 4: 5; and (d) the modified silica substrate contains silicon dioxide with a degree of purity of at least about 95%, modified with calcium metasilicate in an amount of at least about 2.5% to about 10% of the mass.

Embodiment No. 36 is a method of Embodiment No. 35, wherein the amount of platinum present is at least 1% by weight.

Embodiment No. 37 is a method of Embodiment No. 2, carried out at a temperature of from about 250 ° C to 300 ° C, in which (a) the surface area of the modified silica substrate is at least about 100 m ² / g; (b) the molar ratio of tin to platinum is from about 2: 3 to about 3: 2; and (c) the modified silica substrate contains silicon dioxide with a degree of purity of at least about 95%, modified with calcium metasilicate in an amount of at least about 2.5% to about 10% of the mass.

Embodiment No. 38 is a method of Embodiment No. 37, wherein the amount of platinum present is at least 0.75% by weight.

Embodiment No. 39 is a method of Embodiment No. 38, wherein the catalyst occupies a reactor volume and a gaseous stream containing hydrogen and acetic acid in the vapor phase is passed through said reactor volume at a space velocity of at least about 1000 h ⁻¹ .

Embodiment 40 is a method of Embodiment 38, wherein the catalyst occupies a reactor volume and a gaseous stream containing hydrogen and acetic acid in the vapor phase is passed through said reactor volume at a space velocity of at least about 2500 h ⁻¹ .

Embodiment No. 41 is a method of embodiment No. 40, wherein the amount and oxidation state of platinum and tin, as well as the ratio of platinum to tin and the modified silica support, are controlled so that: (i) at least 90% of the converted acetic acid is converted in ethanol; (ii) less than 2% of acetic acid is converted to compounds other than compounds selected from the group consisting of ethanol, acetaldehyde, ethyl acetate, ethylene and mixtures thereof; (iii) the activity of the catalyst decreased by less than 10%, under the influence of a vaporous mixture of acetic acid and hydrogen at a molar ratio of 10: 1 at a pressure of 2 atm, a temperature of 275 ° C and GHSV 2500 h ^-1 for a period of 336 hours.

Embodiment 42 is the method of Embodiment 38, wherein the catalyst occupies a reactor volume and a gaseous stream containing hydrogen and acetic acid in the vapor phase is passed through said reactor volume at a space velocity of at least about 5000 h ⁻¹ .

Embodiment No. 43 is a method of Embodiment No. 42, wherein the amount and oxidation state of platinum and tin, as well as the ratio of platinum to tin and the modified silica support, are controlled such that: (i) at least 90% of the converted acetic acid is converted in ethanol; (ii) less than 2% of acetic acid is converted to alkanes; (iii) the activity of the catalyst decreased by less than 10%, under the influence of a vaporous mixture of acetic acid and hydrogen at a molar ratio of 10: 1 at a pressure of 2 atm, a temperature of 275 ° C and GHSV 2500 h ^-1 for a period of 168 hours.

Embodiment No. 44 is a method of Embodiment No. 43, carried out at a temperature of from about 250 ° C. to 300 ° C., wherein (a) the surface area of the modified silica substrate is at least about 200 m ² / g; (b) the molar ratio of tin to platinum is from about 5: 4 to about 4: 5; (c) the modified silica substrate contains silicon dioxide with a degree of purity of at least about 95%, the modifier contains calcium silicate in an amount of at least about 2.5% to about 10% of the mass.

An implementation option No. 45 is a method for producing ethanol by reducing acetic acid, comprising passing a gaseous stream containing hydrogen and acetic acid in the vapor phase, with a molar ratio of hydrogen to acetic acid of at least about 4: 1, at a temperature of from about 225 ° C to 300 ° C over a hydrogenation catalyst containing platinum and tin dispersed on an oxide substrate, where the amount and oxidation state of platinum and tin, as well as the ratio of platinum to tin and oxide substrate, are selected t, make up and adjusted so as to: (i) at least 80% of the converted acetic acid was converted to ethanol; (ii) less than 4% of acetic acid is converted to compounds other than compounds selected from the group consisting of ethanol, acetaldehyde, ethyl acetate, ethylene and mixtures thereof; (iii) the activity of the catalyst decreased by less than 10%, under the influence of a vaporous mixture of acetic acid and hydrogen at a molar ratio of 10: 1 at a pressure of 2 atm, a temperature of 275 ° C and GHSV 2500 h ^-1 for a period of 500 hours.

Embodiment 46 is a method of Embodiment 45 wherein the hydrogenation catalyst consists essentially of platinum and tin dispersed on an oxide substrate, and the oxide substrate is a modified oxide substrate, said modified oxide substrate containing an effective amount of a substrate modifier selected from the group consisting of: (i) alkaline earth metal oxides, (ii) alkali metal oxides, (iii) alkaline earth metal metasilicates, (iv) metashi alkali metal licates, (v) zinc oxide, (vi) zinc metasilicate and (vii) precursors of any of (i) to (vi), and mixtures of any of (i) to (vii).

Embodiment No. 47 is a method of Embodiment No. 46, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment No. 48 is the method of Embodiment No. 47, wherein (a) platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; and (b) tin is present in an amount of at least 0.5 to 10%.

Embodiment No. 49 is a method of Embodiment No. 47, wherein the molar ratio of platinum to tin is from 4: 5 to 5: 4.

Embodiment No. 50 is the method of Embodiment No. 46, wherein the substrate modifier is selected from the group consisting of metasilicates of sodium, potassium, magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

An implementation option No. 51 is a method of an implementation option No. 50, in which (a) platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; and (b) tin is present in an amount of at least 0.5 to 10%.

Embodiment No. 52 is a method of Embodiment No. 51, wherein the molar ratio of platinum to tin is from 4: 5 to 5: 4.

Embodiment No. 53 is the method of Embodiment No. 46, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment No. 54 is the method of Embodiment No. 53, wherein (a) platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; and (b) tin is present in an amount of at least 0.5 to 10%.

Embodiment No. 55 is a method of Embodiment No. 54, wherein the molar ratio of platinum to tin is from 4: 5 to 5: 4.

Embodiment No. 56 is a method of Embodiment No. 46 wherein the substrate modifier is selected from the group consisting of metasilicates of magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment No. 57 is the method of Embodiment No. 56, wherein (a) platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; and (b) tin is present in an amount of at least 0.5 to 10%.

Embodiment No. 58 is a method of Embodiment No. 57, wherein the molar ratio of platinum to tin is from 4: 5 to 5: 4.

Embodiment No. 59 is a method of Embodiment No. 46 wherein the substrate modifier is selected from the group consisting of calcium metasilicate, calcium metasilicate precursors, and mixtures of calcium metasilicate and its precursors.

An implementation option No. 60 is a method of an implementation option No. 59, in which (a) platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; and (b) tin is present in an amount of at least 0.5 to 10%.

Option exercise No. 61 is the method of embodiment No. 60, in which the molar ratio of platinum to tin is from 4: 5 to 5: 4.

Embodiment 62 is a method of Embodiment 46, wherein (a) platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; and (b) tin is present in an amount of at least 0.5 to 10%.

An implementation option No. 63 is a method of an implementation option No. 62, in which the molar ratio of platinum to tin is from 4: 5 to 5: 4.

Embodiment 64 is the method of Embodiment 62, wherein the surface area of the substrate is at least about 100 m ² / g.

Embodiment No. 65 is a method of Embodiment No. 64, wherein the molar ratio of tin to platinum group metal is from about 1: 2 to about 2: 1.

Embodiment No. 66 is a method of Embodiment No. 64, wherein the molar ratio of tin to platinum is from about 2: 3 to about 3: 2.

Option exercise No. 67 is the method of embodiment No. 64, in which the mass ratio of tin to platinum is from about 5: 4 to about 4: 5.

Embodiment No. 68 is a method of Embodiment No. 46 wherein the surface area of the substrate is at least about 150 m ² / g.

An implementation option No. 69 is a method of an implementation option No. 68, in which (a) platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; and (b) tin is present in an amount of at least 0.5 to 5%.

An implementation option No. 70 is a method of an implementation option No. 68, in which the substrate contains at least about 1% to about 10% of the mass. calcium silicate.

Embodiment No. 71 is the method of Embodiment No. 68, wherein the molar ratio of tin to platinum is from about 1: 2 to about 2: 1.

Embodiment 72 is a method of Embodiment 68, wherein the molar ratio of tin to platinum is from about 2: 3 to about 3: 2.

Embodiment 73 is a method of Embodiment 68, wherein the mass ratio of tin to platinum is from about 5: 4 to about 4: 5.

Embodiment No. 74 is the method of Embodiment No. 46, wherein the surface area of the substrate is at least about 200 m ² / g.

Embodiment No. 75 is the method of Embodiment No. 74, wherein the molar ratio of tin to platinum is from about 2: 3 to about 3: 2.

Embodiment No. 76 is the method of Embodiment No. 74, wherein the molar ratio of tin to platinum is from about 5: 4 to about 4: 5.

Embodiment No. 77 is a method of Embodiment No. 74, wherein the molar ratio of tin to platinum is from about 9:10 to about 10: 9.

An implementation option No. 78 is a method for producing ethanol by reducing acetic acid, comprising passing a gaseous stream containing hydrogen and acetic acid in the vapor phase, with a molar ratio of hydrogen to acetic acid of at least about 4: 1, at a temperature of from about 225 ° C to 300 ° C over a hydrogenation catalyst consisting essentially of platinum and tin dispersed on a modified stabilized silica support, wherein the modified stabilized silica i the substrate contains silicon dioxide with a purity of at least about 95% by weight, modified with a stabilizer-modifier selected from the group consisting of: (i) alkaline earth metal oxides, (ii) alkaline metal oxides, (iii) alkaline earth metasilicates metals, (iv) alkali metal metasilicates, (v) zinc oxide, (vi) zinc metasilicate and (vii) precursors of any of (i) - (vi), and mixtures of any of (i) - (vii), where the oxidation state of platinum and tin, the ratio of platinum to tin, and the ratio of stabilizer-modifier to dio silicon seed in a modified stabilized silica substrate, as well as the degree of purity of silicon dioxide in a modified stabilized silica substrate, is controlled so that at least 80% of the converted acetic acid is converted to ethanol and less than 4% of acetic acid is converted to compounds, others, than compounds selected from the group consisting of ethanol, acetaldehyde, ethyl acetate, ethylene and mixtures thereof.

Embodiment No. 79 is the method of Embodiment No. 78, wherein (a) platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; and (b) tin is present in an amount of at least 0.5 to 10%.

Embodiment 80 is the method of Embodiment 79, wherein the surface area of the modified stabilized silica substrate is at least about 100 m ² / g.

Embodiment No. 81 is a method of Embodiment No. 80, wherein the molar ratio of tin to platinum group metal is from about 1: 2 to about 2: 1.

Embodiment No. 82 is a method of Embodiment No. 80, wherein the molar ratio of tin to platinum is from about 2: 3 to about 3: 2.

Embodiment No. 83 is the method of Embodiment No. 79, wherein the mass ratio of tin to platinum is from about 5: 4 to about 4: 5.

Embodiment No. 84 is the method of Embodiment No. 78, wherein the surface area of the modified stabilized silica substrate is at least about 150 m ² / g.

Embodiment No. 85 is a method of Embodiment No. 84, wherein (a) platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; and (b) tin is present in an amount of at least 0.5 to 5%.

Embodiment No. 86 is a method of Embodiment No. 84, wherein the modified stabilized silica substrate comprises at least about 1% to about 10% by weight. calcium silicate.

Embodiment No. 87 is a method of Embodiment No. 84, wherein the molar ratio of tin to platinum is from about 1: 2 to about 2: 1.

Embodiment No. 88 is the method of Embodiment No. 84, wherein the molar ratio of tin to platinum is from about 2: 3 to about 3: 2.

Embodiment No. 89 is a method of Embodiment No. 84, wherein the mass ratio of tin to platinum is from about 5: 4 to about 4: 5.

Embodiment No. 90 is the method of Embodiment No. 87, wherein the surface area of the modified stabilized silica substrate is at least about 200 m ² / g.

Embodiment No. 91 is a method of Embodiment No. 90 wherein the molar ratio of tin to platinum is from about 9:10 to about 10: 9.

Embodiment 92 is a method of Embodiment 90, wherein the molar ratio of tin to platinum is from about 2: 3 to about 3: 2.

Embodiment 93 is a method of Embodiment 90 wherein the molar ratio of tin to platinum is from about 5: 4 to about 4: 5.

Embodiment No. 94 is the method of Embodiment No. 90, wherein the surface area of the modified stabilized silica substrate is at least about 250 m ² / g.

Embodiment No. 95 is a method of Embodiment No. 78, carried out at a temperature of from about 250 ° C. to 300 ° C., wherein (a) the surface area of the modified stabilized silica substrate is at least about 250 m ² / g; (b) platinum is present in the hydrogenation catalyst in an amount of at least about 0.75% by weight .; (c) the molar ratio of tin to platinum is from about 5: 4 to about 4: 5; and (d) the modified stabilized silica substrate contains at least about 2.5% to about 10% of the mass. calcium silicate.

Embodiment No. 96 is a method of Embodiment No. 95 wherein the amount of platinum present is at least 1% by weight.

Embodiment No. 97 is a method of Embodiment No. 78, carried out at a temperature of from about 250 ° C. to 300 ° C., wherein (a) the surface area of the modified stabilized silica substrate is at least about 100 m ² / g; (b) the molar ratio of tin to platinum is from about 2: 3 to about 3: 2; and (c) the modified stabilized silica substrate contains at least about 2.5% to about 10% of the mass. calcium silicate.

Option exercise No. 98 is a method of embodiment No. 97, in which the amount of platinum present is at least 0.75% of the mass.

Embodiment No. 99 is a method of Embodiment No. 98, wherein the catalyst occupies a reactor volume, and a gaseous stream containing hydrogen and acetic acid in the vapor phase is passed through said reactor volume at a space velocity of at least about 1000 h ⁻¹ .

Embodiment No. 100 is a method of Embodiment No. 98, wherein the catalyst occupies a reactor volume and a gaseous stream containing hydrogen and acetic acid in the vapor phase is passed through said reactor volume at a space velocity of at least about 2500 h ⁻¹ .

Embodiment No. 101 is a method of Embodiment No. 100 wherein the amount and oxidation state of platinum and tin, as well as the ratio of platinum to tin and the composition of the modified stabilized silica support are controlled so that at least 90% of the converted acetic acid is converted to ethanol, and less than 2% acetic acid, was converted to compounds other than compounds selected from the group consisting of ethanol, acetaldehyde, ethyl acetate, ethylene, and mixtures thereof.

Embodiment No. 102 is a method of Embodiment No. 98, wherein the catalyst occupies a reactor volume and a gaseous stream containing hydrogen and acetic acid in the vapor phase is passed through said reactor volume at a space velocity of at least about 5000 h ⁻¹ .

Embodiment No. 103 is a method of Embodiment No. 79 wherein the amount and oxidation state of platinum and tin, as well as the ratio of platinum to tin and the composition of the modified stabilized silica support are controlled so that at least 90% of the converted acetic acid is converted to ethanol, and less than 2% of acetic acid was converted to alkanes.

Embodiment No. 104 is a method of Embodiment No. 79, carried out at a temperature of from about 250 ° C. to 300 ° C., wherein (a) the amount and oxidation state of platinum and tin, as well as the ratio of platinum to tin and the acidity of the modified stabilized silica substrate adjusted so that at least 90% of the converted acetic acid is converted to ethanol, and less than 1% of the acetic acid is converted to alkanes; (b) the surface area of the modified stabilized silica substrate is at least about 200 m ² / g; (c) the molar ratio of tin to platinum is from about 5: 4 to about 4: 5; (d) the modified stabilized silica substrate contains at least about 2.5% to about 10% of the mass. calcium silicate.

An implementation option No. 105 is a method of producing ethanol by reducing acetic acid, comprising passing a gaseous stream containing hydrogen and acetic acid in the vapor phase, with a molar ratio of hydrogen to acetic acid of at least about 4: 1, at a temperature of from about 225 ° C to 300 ° C over a hydrogenation catalyst consisting essentially of: Fe, Co, Cu, Ni, Ru, Rh, Pd, Ir, Pt, Sn, Re, Os, Ti, Zn, Cr, Mo and W , as well as mixtures thereof in an amount of from about 0.1% to about 10% of the mass .; and an optional promoter dispersed on a suitable support, wherein the amount and oxidation state of the catalytically active metal (s) and the support and optional promoter compositions are controlled so that: (i) at least 80% of the converted acetic acid is converted to ethanol; (ii) less than 4% of acetic acid is converted to compounds other than compounds selected from the group consisting of ethanol, acetaldehyde, ethyl acetate, ethylene, diethyl ether and mixtures thereof; (iii) the activity of the catalyst decreased by less than 10%, under the influence of a vaporous mixture of acetic acid and hydrogen at a molar ratio of 10: 1 at a pressure of 2 atm, a temperature of 275 ° C and GHSV 2500 h ^-1 for a period of 500 hours.

Embodiment No. 106 is a method of Embodiment No. 105 wherein the substrate is an oxide substrate modified with a modifier selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium, scandium, yttrium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment 107 is a method of Embodiment 105 wherein the substrate is a carbon substrate and the catalytically active metals include platinum and tin.

Embodiment No. 108 is the method of Embodiment No. 107, wherein the carbon substrate is modified with a reducible metal oxide.

An implementation option No. 109 is a method of producing ethanol by reducing acetic acid, comprising passing a gaseous stream containing hydrogen and acetic acid in the vapor phase, with a molar ratio of hydrogen to acetic acid of at least about 4: 1, at a temperature of from about 225 ° C to 300 ° C over a hydrogenation catalyst consisting essentially of metal components dispersed on an oxide support, wherein said hydrogenation catalyst has the composition:

Pt _v Pd _w Re _x Sn _y Al _z Ca _p Si _q O _r ,

where the ratio v: y is from 3: 2 to 2: 3; the ratio w: x is from 1: 3 to 1: 5, p and z, and the relative position of the aluminum and calcium atoms present is controlled so that the centers of the Bransted acids present on the surface are balanced by calcium silicate; p and q are chosen so that p: q is from 1:20 to 1: 200, with r chosen so that the valence requirements are satisfied, v and w are chosen so that

≤0,05.0.005≤ $$\frac{(3.25v+1.75w)}{q}$$

≤0.05.

Embodiment No. 110 is the method of Embodiment No. 109, wherein the surface area of the hydrogenation catalyst is at least about 100 m ² / g, and in which z and p are adjusted so that p≥z.

Embodiment No. 111 is the method of Embodiment No. 110, wherein p, taking into account any small amount of impurities present, is selected so that substantially free Bransted acid sites are absent on the surface of the substrate.

An implementation option No. 112 is a method of hydrogenation of acetic acid, comprising passing a gaseous stream containing hydrogen and acetic acid in the vapor phase, with a molar ratio of hydrogen to acetic acid of at least about 4: 1, at a temperature of from about 225 ° C to 300 ° C. above the hydrogenation catalyst, consisting essentially of: a catalytically active metal selected from the group consisting of: Fe, Co, Cu, Ni, Ru, Rh, Pd, Ir, Pt, Sn, Re, Os, Ti , Zn, Cr, Mo and W, as well as mixtures thereof in an amount of from about 0.1% to about 10% by weight .; and an optional promoter dispersed on an appropriate support, wherein the amount and oxidation state of the catalytically active metal (s) and the support and optional promoter compositions, as well as the reaction conditions, are controlled so that less than 4% of the acetic acid is converted to compounds other than the compounds, selected from the group consisting of ethanol, acetaldehyde, ethyl acetate, ethylene, diethyl ether and mixtures thereof; and the activity of the catalyst decreased by less than 10%, under the influence of a vaporous mixture of acetic acid and hydrogen at a molar ratio of 10: 1 at a pressure of 2 atm, a temperature of 275 ° C and GHSV 2500 h ^-1 for a period of 500 hours, with additional conditions: ( i) the substrate is an oxide substrate modified with a modifier selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium, scandium, yttrium and zinc, as well as their precursors and mixtures of any of these compounds; (ii) the support is a carbon support and the catalytically active metals include platinum and tin; or (iii) the support is a carbon support modified with a reducible metal oxide.

An implementation option No. 113 is a method of hydrogenation of acetic acid, comprising passing a gaseous stream containing hydrogen and acetic acid in the vapor phase, with a molar ratio of hydrogen to acetic acid of at least about 2: 1, at a temperature of from about 125 ° C to 350 ° C above a hydrogenation catalyst containing: a platinum group metal selected from the group consisting of platinum, palladium, rhenium and mixtures thereof, on a silica substrate selected from the group consisting of silicon dioxide, calcium metasilicate cation and silicon dioxide promoted with calcium metasilicate; and the promoter is selected from the group consisting of tin and rhenium and mixtures thereof, wherein the silica substrate is optionally promoted with a promoter selected from the group consisting of (a) a promoter selected from the group consisting of alkali metals, alkaline earth metals and zinc, in an amount of 1-5% by weight of the catalyst; (b) a redox promoter selected from the group consisting of WO ₃ , MoO ₃ , Fe ₂ O ₃ and Cr ₂ O ₃ , in an amount of 1-50% by weight of the catalyst; and (c) an acidity modifier selected from the group consisting of TiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ and Al ₂ O ₃ , in an amount of 1-50% by weight of the catalyst.

Embodiment No. 114 is a method of Embodiment No. 113, wherein said alkanoic acid is acetic acid, and in which (a) at least one of platinum and palladium is present in an amount of from 0.25% to 5% by weight a catalyst; (b) the total amount of platinum and palladium present is at least 0.5% by weight of the catalyst; (c) the total amount of rhenium and tin present is at least 0.5 to 10% by weight.

Embodiment No. 115 is a method of Embodiment No. 114, wherein the surface area of the silica substrate is at least about 150 m ² / g.

Embodiment No. 116 is the method of Embodiment No. 115, wherein (a) the amount and oxidation state of the platinum group metals, rhenium and tin promoters, and (b) the molar ratio of the platinum group metal to the total molar amount of rhenium and tin present; and (c) the number of Bransted acid centers on the surface of the silica support is controlled so that at least 80% of the converted acetic acid is converted to a compound selected from the group consisting of ethanol and ethyl acetate, while less than 4% of acetic acid is converted to compounds other than compounds selected from the group consisting of ethanol, acetaldehyde, ethyl acetate, ethylene and mixtures thereof.

Embodiment No. 117 is a method of Embodiment No. 115, wherein (a) at least one of platinum and palladium is present in an amount of from 0.5% to 5% by weight of the catalyst; (b) the total amount of platinum and palladium present is at least 0.75% to 5% by weight of the catalyst; (c) the total amount of rhenium and tin present is at least 1.0% by weight of the catalyst.

Embodiment No. 118 is the method of Embodiment No. 117, wherein (a) the amount and oxidation state of (i) platinum group metals, (ii) rhenium and tin promoters, and (iii) the molar ratio of the platinum group metal to rhenium promoters and tin; and (iv) the acidity of the silica support is controlled so that at least 80% of the converted acetic acid is converted to ethanol and less than 4% of the acetic acid is converted to compounds other than compounds selected from the group consisting of ethanol, acetaldehyde, ethyl acetate, ethylene and mixtures thereof.

Embodiment No. 119 is the method of Embodiment No. 118, wherein the total mass of rhenium and tin present is from about 1 to 10% by weight of the catalyst.

Embodiment 120 is a method of Embodiment 119, wherein the molar ratio of the platinum group metal to the total molar amount of rhenium and tin is from about 1: 2 to about 2: 1.

Option exercise No. 121 is a method of hydrogenation of acetic acid, comprising passing a gaseous stream containing hydrogen and acetic acid in the vapor phase, with a molar ratio of hydrogen to acetic acid of at least about 4: 1, at a temperature of from about 225 ° C to 300 ° C above the hydrogenation catalyst, consisting essentially of metal components dispersed on an oxide substrate, while the specified hydrogenation catalyst has the composition:

Pt _v Pd _w Re _x Sn _y Ca _p Si _q O _r ,

where the ratio v: y is from 3: 2 to 2: 3; the ratio w: x is from 1: 3 to 1: 5, p and q are chosen so that p: q is from 1:20 to 1: 200, with r chosen so that the valence requirements are satisfied, v and w are selected so that

≤0,05.0.005≤ $$\frac{(3.25v+1.75w)}{q}$$

≤0.05.

Embodiment No. 122 is the method of Embodiment No. 121, wherein the conditions of the method and the quantities v, w, x, y, p, q and r are selected so that at least 90% of the converted acetic acid is converted to the compounds selected from the group consisting of ethanol and ethyl acetate, while less than 4% of acetic acid was converted to alkanes.

Embodiment No. 123 is a method of Embodiment No. 122 wherein the conditions of the method and the quantities v, w, x, y, p, q and r are selected such that at least 90% of the converted acetic acid is converted to ethanol, and less than 2% of acetic acid is converted to alkanes.

Embodiment No. 124 is the method of Embodiment No. 122, wherein p, taking into account any small amount of impurities present, is selected such that the surface of the substrate is substantially basic.

An implementation option No. 125 is a method of hydrogenation of acetic acid, comprising passing a gaseous stream containing hydrogen and acetic acid in the vapor phase, with a molar ratio of hydrogen to acetic acid of at least about 4: 1, at a temperature of from about 225 ° C to 300 ° C above the hydrogenation catalyst, consisting essentially of metal components dispersed on an oxide substrate, while the specified hydrogenation catalyst has the composition:

Pt _v Pd _w Re _x Sn _y Al _z Ca _p Si _q O _r ,

where the ratio v: y is from 3: 2 to 2: 3; the ratio w: x is from 1: 3 to 1: 5, p and z, and the relative position of the aluminum and calcium atoms present is controlled so that the centers of the Bransted acids present on the surface are balanced by calcium silicate; p and q are chosen so that p: q is from 1:20 to 1: 200, with r chosen so that the valence requirements are satisfied, v and w are chosen so that

≤0,05.0.005≤ $$\frac{(3.25v+1.75w)}{q}$$

≤0.05.

Embodiment No. 126 is the method of Embodiment No. 125, wherein the surface area of the hydrogenation catalyst is at least about 100 m ² / g, and in which z and p are adjusted so that p≥z.

Embodiment No. 127 is the method of Embodiment No. 125, wherein p, taking into account any small amount of impurities present, is selected so that substantially free Bransted acid sites are absent on the surface of the substrate.

Embodiment No. 128 is a method for hydrogenating alkanoic acids, comprising passing a gaseous stream containing hydrogen and alkanoic acid in the vapor phase, with a molar ratio of hydrogen to alkanoic acid of at least about 5: 1, at a temperature of from about 125 ° C to 350 ° C., a GHSV of at least about 1000 h ⁻¹ , a pressure of at least 2 atmospheres above the hydrogenation catalyst, wherein said hydrogenation catalyst contains (a) a platinum group metal selected from the group consisting of platinum, palladium and mixtures thereof, on a silica support selected from the group consisting of silicon dioxide, calcium metasilicate and silicon dioxide promoted with calcium metasilicate; and (b) a metal promoter selected from the group consisting of tin and rhenium and mixtures thereof, (c) a silica substrate, optionally promoted with a second promoter selected from the group consisting of (i) a donor promoter selected from the group consisting of alkaline metals, alkaline earth elements and zinc, in an amount of 1-5% by weight of the catalyst; (ii) a redox promoter selected from the group consisting of WO ₃ , MoO ₃ , Fe ₂ O ₃ and Cr ₂ O ₃ , in an amount of 1-50% by weight of the catalyst; (iii) an acidity modifier selected from the group consisting of TiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ and Al ₂ O ₃ , in an amount of 1-50% by weight of the catalyst; and (iv) combinations of i, ii, and iii.

Embodiment No. 129 is the method of Embodiment No. 128, wherein said alkanoic acid is acetic acid, and where (a) platinum, if present, is present in an amount of from 0.5% to 5% by weight of the catalyst; (b) palladium, if present, is present in an amount of from 0.5% to 5% by weight of the catalyst; and (c) a metal promoter, if present, is present in an amount of at least 0.5% to 10%.

Embodiment 130 is the method of Embodiment 129, wherein the surface area of the silica substrate is at least about 150 m ² / g.

Option exercise No. 131 is the method of embodiment No. 130, in which (a) platinum is present in an amount of from 1% to 5% by weight of the catalyst; (b) palladium, if present, is present in an amount of from 0.25% to 5% by weight of the catalyst; and (c) the total amount of platinum and palladium is at least 1.25% by weight of the catalyst.

Embodiment No. 132 is the method of Embodiment No. 131, in which tin is present in an amount of 1-3% by weight of the catalyst.

Embodiment No. 133 is a method of Embodiment No. 132, wherein the molar ratio of tin to platinum group metal is from about 1: 2 to about 2: 1.

Embodiment No. 134 is a method of Embodiment No. 132, wherein the molar ratio of tin to platinum is from about 5: 4 to about 4: 5.

Embodiment No. 135 is a method of Embodiment No. 132, wherein the silica substrate is substantially free of Bransted acid centers unbalanced by calcium metasilicate and its surface area is at least about 200 m ² / g.

Embodiment No. 136 is a method of Embodiment No. 132, wherein the mass ratio of tin to platinum group metal is from about 2: 3 to about 3: 2.

Embodiment No. 137 is a method of Embodiment No. 128, wherein the molar ratio of tin to platinum is from about 2: 3 to about 3: 2.

An implementation option No. 138 is a method of hydrogenation of acetic acid, comprising passing a gaseous stream containing hydrogen and acetic acid in the vapor phase, with a molar ratio of hydrogen to acetic acid of at least about 4: 1, at a temperature of from about 225 ° C to 300 ° C. above the hydrogenation catalyst, consisting essentially of: a catalytically active metal selected from the group consisting of: Fe, Co, Cu, Ni, Ru, Rh, Pd, Ir, Pt, Sn, Re, Os, Ti , Zn, Cr, Mo and W, as well as mixtures thereof in an amount of from about 0.1% to about 10% by weight .; and an optional promoter dispersed on an appropriate support, wherein the amount and oxidation state of the catalytically active metal (s) and the support and optional promoter compositions, as well as the reaction conditions, are controlled so that less than 4% of the acetic acid is converted to compounds other than the compounds, selected from the group consisting of ethanol, acetaldehyde, ethyl acetate, ethylene, diethyl ether and mixtures thereof; and the activity of the catalyst decreased by less than 10%, under the influence of a vaporous mixture of acetic acid and hydrogen at a molar ratio of 10: 1 at a pressure of 2 atm, a temperature of 275 ° C and GHSV 2500 h ^-1 for a period of 500 hours.

Embodiment No. 129 is a method of Embodiment No. 138, wherein the substrate is selected from: substrates representing molecular sieves, modified silica substrates modified with a modifier selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium, scandium , yttrium and zinc, as well as their precursors and mixtures of any of these compounds, and carbon substrates.

Embodiment 140 is the method of Embodiment 139, wherein the catalytically active metals include platinum and tin, and the selectivity for diethyl ether is more than 80%.

Embodiment No. 141 is a method of Embodiment No. 107, wherein the substrate is a zeolite substrate and the selectivity for diethyl ether is more than 90%.

An implementation option No. 142 is a method for producing ethanol and ethyl acetate by reducing acetic acid, comprising passing a gaseous stream containing hydrogen and acetic acid in the vapor phase, with a molar ratio of hydrogen to acetic acid of at least about 4: 1, at a temperature of about from 225 ° C to 300 ° C over a hydrogenation catalyst containing: (a) a platinum group metal selected from the group consisting of platinum and mixtures of platinum and palladium on a silica substrate selected from the group consisting of her from silicon dioxide and silicon dioxide promoted with calcium metasilicate in an amount of up to about 7.5%, where the amount of platinum group metal present is at least about 2.0%, the amount of platinum present is at least about 1, 5%; and (b) a metal promoter selected from the group consisting of tin and rhenium in an amount of from about 1% to 2% by weight of the catalyst, wherein the molar ratio of platinum to metal promoter is from about 3: 1 to 1: 2; (c) a silica support, optionally promoted with a second promoter selected from the group consisting of (i) a donor promoter selected from the group consisting of alkali metals, alkaline earth elements and zinc, in an amount of 1-5% by weight of the catalyst; (ii) a redox promoter selected from the group consisting of WO ₃ , MoO ₃ , Fe ₂ O ₃ and Cr ₂ O ₃ , in an amount of 1-50% by weight of the catalyst; (iii) an acidity modifier selected from the group consisting of TiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ and Al ₂ O ₃ , in an amount of 1-50% by weight of the catalyst; and (iv) combinations of i, ii, and iii.

Embodiment No. 142 is a method of embodiment No. 142, wherein the molar ratio of the metal promoter to the platinum group metal is from about 2: 3 to about 3: 2.

Embodiment No. 144 is the method of Embodiment No. 142, wherein the molar ratio of the metal promoter to the platinum group metal is from about 5: 4 to about 4: 5.

Embodiment No. 145 is the method of Embodiment No. 142, wherein the surface area of the silica substrate is at least about 200 m ² / g and the amount of calcium metasilicate is sufficient to turn the surface of the silica substrate into substantially free from Bransted acidity.

Embodiment No. 146 is a method of Embodiment No. 145, wherein the molar ratio of the metal promoter to the platinum group metal is from about 2: 3 to about 3: 2.

Embodiment 147 is a method of Embodiment 146 wherein the surface area of the silica substrate is at least about 200 m ² / g and the number of moles of Bransted acid centers present on its surface does not exceed the number of moles of Bransted acid centers present on the surface of the silica Saint-Gobain NorPro SS61138.

Embodiment No. 148 is the method of Embodiment No. 142, wherein the surface area of the silica substrate is at least about 250 m ² / g and the number of moles of Bransted acid centers present on its surface does not exceed half the number of moles of acid centers Branstead present on the surface of the silica Saint-Gobain NorPro HSA SS61138.

Embodiment No. 149 is a method of Embodiment No. 142, carried out at a temperature of from about 250 ° C to 300 ° C, in which (a) the hydrogenation catalyst contains palladium on a silica substrate selected from the group consisting of silicon dioxide and silicon dioxide, promoted with calcium metasilicate in an amount of up to about 7.5%, where the amount of palladium present is at least about 1.5%; (b) the metal promoter is rhenium in an amount of about 1% to 10% by weight of the catalyst, wherein the molar ratio of rhenium to palladium is about 3: 1 to about 5: 1.

Embodiment 150 is a method of reducing acetic acid of Embodiment 142, wherein the hydrogenation catalyst consists essentially of platinum on a silica substrate consisting essentially of silicon dioxide promoted with calcium silicate in an amount of about 3% to about 7.5%, where the amount of platinum present is at least about 1.0%, and the tin promoter in an amount of about 1% to 5% by weight of the catalyst, while the molar ratio of platinum to tin is approximately but from 9:10 to 10: 9.

Embodiment No. 151 is a method of reducing acetic acid of Embodiment No. 142, wherein the amount of platinum group metal present is at least about 2.0%, the amount of platinum present is at least about 1.5%, and the tin promoter is present in an amount of from about 1% to 5% by weight of the catalyst, while the molar ratio of platinum to tin is from about 9:10 to 10: 9.

Embodiment No. 152 is a method of Embodiment No. 151, conducted at a temperature of from about 250 ° C. to 300 ° C., wherein said hydrogenation catalyst comprises: 2.5 to 3.5 mass. percent platinum, from 2% of the mass. up to 5% of the mass. tin dispersed on silica with a highly developed surface, the surface area of which is at least 200 m ² per gram, while the specified silica with a highly developed surface is promoted by calcium metasilicate in an amount of from about 4% to 7.5% .

Embodiment No. 153 is a method for producing a stream containing ethanol and at least about 40% ethyl acetate by reducing acetic acid, comprising passing a gaseous stream containing hydrogen and acetic acid in the vapor phase, with a molar ratio of hydrogen to acetic acid, at least about 4: 1, at a temperature of from about 225 ° C. to 300 ° C. over a hydrogenation catalyst consisting essentially of metal components dispersed on an oxide support, wherein said kata hydrogenation lyser has the composition:

Pt _v Pd _w Re _x Sn _y Al _z Ti _n Ca _p Si _q O _r ,

where the ratio v: y is from 3: 2 to 2: 3; the w: x ratio is from 1: 3 to 1: 5, and where p and z and p, q and n are chosen so that

≤0,2,0.005≤ $$\frac{2p}{q+1.33n+1.77z}$$

≤0.2

for r chosen so that the valence requirements are satisfied, and v and w chosen so that

≤0,05.0.005≤ $$\frac{(3.25v+1.75w)}{q+1.33n+1.77z}$$

≤0.05.

Embodiment No. 154 is a method of Embodiment No. 153, wherein the surface area of the hydrogenation catalyst is at least about 100 m ² / g.

An implementation option No. 155 is a method of hydrogenation of acetic acid, comprising passing a gaseous stream containing hydrogen and acetic acid in the vapor phase, with a molar ratio of hydrogen to acetic acid of at least about 4: 1, at a temperature of from about 225 ° C to 300 ° C. above the hydrogenation catalyst, consisting essentially of: a catalytically active metal selected from the group consisting of: Fe, Co, Cu, Ni, Ru, Rh, Pd, Ir, Pt, Sn, Re, Os, Ti , Zn, Cr, Mo and W, as well as mixtures thereof in an amount of from about 0.1% to about 10% by weight .; and an optional promoter dispersed on a suitable support, wherein the amount and oxidation state of the catalytically active metal (s) and the composition of the support and optional promoter, as well as the reaction conditions are controlled such that: (i) more than 50% of the converted acetic acid is converted to ethyl acetate; (ii) less than 4% of acetic acid is converted to compounds other than compounds selected from the group consisting of ethanol, acetaldehyde, ethyl acetate, ethylene, diethyl ether and mixtures thereof; (iii) the activity of the catalyst decreases by less than 10%, under the influence of a vaporous mixture of acetic acid and hydrogen at a molar ratio of 10: 1 at a pressure of 2 atm, a temperature of 275 ° C and GHSV 2500 h ^-1 for a period of 500 hours.

Embodiment No. 156 is a particulate catalyst for hydrogenation of alkanoic acids to the corresponding aliphatic alcohol, comprising: (a) a platinum group metal selected from the group consisting of platinum, palladium and mixtures thereof, on a silica support selected from the group consisting of from silicon dioxide and silicon dioxide, promoted with calcium metasilicate in an amount of from about 3.0 to about 7.5%, while the surface area of the silica substrate is at least about 150 m ² / g; and (b) a tin promoter in an amount of from about 1% to 3% by weight of the catalyst, wherein the molar ratio of platinum to tin is from about 4: 3 to 3: 4; (c) the composition and structure of the silica substrate are selected so that on its surface there are essentially no Bransted acid centers not balanced by calcium metasilicate.

Embodiment No. 157 is a hydrogenation catalyst of Embodiment No. 156, in which the total mass of platinum group metals present is from 2 to 4%, the amount of platinum present is at least 2%, the mass ratio of platinum to tin is from 4: 5 to 5: 4, the amount of calcium silicate present is from 3 to 7.5%.

Embodiment No. 158 is a hydrogenation catalyst consisting essentially of: a silica support on which a platinum group metal is selected, selected from the group consisting of platinum, palladium and mixtures thereof, with a promoter selected from the group consisting of tin, cobalt and rhenium, wherein the surface area of the silica substrate is at least about 175 m ² / g, and the silica substrate is selected from the group consisting of silicon dioxide, calcium metasilicate and silicon dioxide, meta calcium silicate, where the calcium metasilicate is dispersed on its surface, and on the surface of the silica substrate, there are essentially no Bransted acid centers resulting from the presence of calcium unbalanced alumina.

Embodiment No. 159 is a hydrogenation catalyst of Embodiment No. 158, in which the total mass of the platinum group metals present is from 0.5 to 2%, the amount of palladium present is at least 0.5%, the rhenium promoter, mass ratio rhenium to palladium is from 10: 1 to 2: 1, the amount of calcium metasilicate present is from 3 to 90%.

Embodiment No. 160 is a hydrogenation catalyst of Embodiment No. 159, in which the total mass of platinum group metals present is from 0.5 to 2%, the amount of platinum present is at least 0.5%, the promoter is cobalt, mass ratio cobalt to platinum is from 20: 1 to 3: 1, the amount of calcium silicate is from 3 to 90%.

Embodiment No. 161 is a hydrogenation catalyst of Embodiment No. 158, in which the total mass of platinum group metals present is from 0.5 to 2%, the amount of palladium present is at least 0.5%, the promoter is cobalt, mass ratio cobalt to palladium is from 20: 1 to 3: 1, the amount of calcium silicate is from 3 to 90%.

An implementation option No. 162 is a hydrogenation catalyst containing: from 2.5 to 3.5 mass. percent platinum, from 3% of the mass. up to 5% of the mass. tin dispersed on fumed silica with a highly developed surface, the surface area of which is at least 200 m ² per gram, while said silica with a highly developed surface is promoted by calcium metasilicate in an amount of about 4% to 6%, the molar ratio of platinum to tin is from 4: 5 to 5: 4.

An implementation option No. 163 is a hydrogenation catalyst containing: from 0.5 to 2.5 mass. percent palladium, from 2% of the mass. up to 7% of the mass. rhenium, with a mass ratio of rhenium to palladium of at least 1.5: 1.0, wherein said rhenium and palladium are dispersed on a silica substrate, said silica substrate contains at least 80% calcium metasilicate.

Embodiment No. 164 is a particulate catalyst for hydrogenation of alkanoic acids to the corresponding aliphatic alcohol, comprising: (a) a platinum group metal selected from the group consisting of platinum, palladium and mixtures thereof, on a silica support selected from the group consisting of from a modified stabilized silica substrate, wherein said silica substrate is modified and stabilized by a stabilizer-modifier selected from the group consisting of (i) alkaline earth oxides metals, (ii) alkali metal oxides, (iii) alkaline earth metal metasilicates, (iv) alkali metal metasilicates, (v) zinc oxide, (vi) zinc metasilicate and (vii) precursors of any of compounds (i) to (vi), and mixtures of any of (i) to (vii), the surface area of the modified stabilized silica substrate is at least about 150 m ² / g; and (b) a tin promoter in an amount of about 1% to 3% by weight of the catalyst, with a platinum to tin molar ratio of about 4: 3 to 3: 4.

Embodiment No. 165 is a hydrogenation catalyst of Embodiment No. 164, in which the total mass of platinum group metals present is from 2 to 4%, the amount of platinum present is at least 2%, the mass ratio of platinum to tin is from 4: 5 up to 5: 4, the amount of stabilizer-modifier present is from 3 to 7.5%.

Embodiment No. 166 is a hydrogenation catalyst of Embodiment No. 165, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment No. 167 is a hydrogenation catalyst of Embodiment No. 165, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium and zinc, as well as their precursors and mixtures of any of the above compounds.

Embodiment No. 168 is a hydrogenation catalyst of Embodiment No. 165, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of magnesium, calcium and zinc, as well as their precursors and mixtures of any of the above compounds.

Embodiment No. 169 is a hydrogenation catalyst of Embodiment No. 165, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment No. 170 is a hydrogenation catalyst of Embodiment No. 165, wherein the substrate modifier is selected from the group consisting of calcium metasilicate, calcium metasilicate precursors, and mixtures of calcium metasilicate and its precursors.

Embodiment No. 171 is a hydrogenation catalyst of Embodiment No. 164, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium and zinc, as well as their precursors and mixtures of any of the above compounds.

Embodiment No. 172 is a hydrogenation catalyst of Embodiment No. 164, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium and zinc, as well as their precursors and mixtures of any of the above compounds.

Embodiment No. 173 is a hydrogenation catalyst of Embodiment No. 164, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment No. 174 is a hydrogenation catalyst of Embodiment No. 164, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment 175 is a hydrogenation catalyst of Embodiment 164, wherein the substrate modifier is selected from the group consisting of calcium metasilicate, calcium metasilicate precursors, and mixtures of calcium metasilicate and its precursors.

Embodiment No. 176 is a particulate catalyst consisting essentially of: a modified stabilized silica support with a platinum group metal dispersed thereon, selected from the group consisting of platinum, palladium and mixtures thereof, with a promoter selected from the group consisting of tin, cobalt and rhenium, while the silica substrate contains silicon dioxide, characterized by a degree of purity of at least 95%, a surface area of at least about 175 m ² / g, modified and stabilized a stabilizer-modifier selected from the group consisting of (i) alkaline earth metal oxides, (ii) alkali metal oxides, (iii) alkaline earth metal metasilicates, (iv) alkaline metal metasilicates, (v) zinc oxide, (vi) zinc metasilicate and (vii) precursors of any of compounds (i) to (vi), and mixtures of any of (i) to (vii), wherein, on the surface of the silica substrate, there are essentially no Bransted acid centers resulting from the presence of alumina, unbalanced stabilizer-modifier.

Embodiment No. 177 is a hydrogenation catalyst of Embodiment No. 176, in which the total mass of platinum group metals present is from 0.5 to 2%, the amount of palladium present is at least 0.5%, the rhenium promoter, mass ratio rhenium to palladium is from 10: 1 to 2: 1, the amount of substrate modifier present is from 3 to 90%.

Embodiment No. 178 is a hydrogenation catalyst of Embodiment No. 177, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment No. 179 is a hydrogenation catalyst of Embodiment No. 177, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment 180 is a hydrogenation catalyst of Embodiment 177, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of magnesium, calcium and zinc, as well as their precursors and mixtures of any of the above compounds.

Embodiment No. 181 is a hydrogenation catalyst of Embodiment No. 177, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment No. 182 is a hydrogenation catalyst of Embodiment No. 177, wherein the substrate modifier is selected from the group consisting of calcium metasilicate, calcium metasilicate precursors, and mixtures of calcium metasilicate and its precursors.

Embodiment No. 183 is a hydrogenation catalyst of Embodiment No. 176, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment No. 184 is a hydrogenation catalyst of Embodiment No. 176, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium and zinc, as well as their precursors and mixtures of any of the above compounds.

Embodiment No. 185 is a hydrogenation catalyst of Embodiment No. 176, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment No. 186 is a hydrogenation catalyst of Embodiment No. 176, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of magnesium, calcium and zinc, as well as their precursors and mixtures of any of the above compounds.

Embodiment No. 187 is a hydrogenation catalyst of Embodiment No. 176, wherein the substrate modifier is selected from the group consisting of calcium metasilicate, calcium metasilicate precursors and mixtures of calcium metasilicate and its precursors.

Embodiment No. 188 is a hydrogenation catalyst of Embodiment No. 176, in which the total mass of platinum group metals present is from 0.5 to 2%, the amount of platinum present is at least 0.5%, the promoter is cobalt, mass ratio cobalt to platinum is from 20: 1 to 3: 1, the amount of substrate modifier is from 3 to 90%.

Embodiment No. 189 is a hydrogenation catalyst of Embodiment No. 188, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment 190 is a hydrogenation catalyst of Embodiment 188, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium and zinc, as well as their precursors and mixtures of any of the above compounds.

Embodiment No. 191 is a hydrogenation catalyst of Embodiment No. 188, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment No. 192 is a hydrogenation catalyst of Embodiment No. 188, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment No. 193 is a hydrogenation catalyst of Embodiment No. 188, wherein the substrate modifier is selected from the group consisting of calcium metasilicate, calcium metasilicate precursors and mixtures of calcium metasilicate and its precursors.

Embodiment No. 194 is a hydrogenation catalyst of Embodiment No. 176, in which the total mass of platinum group metals present is from 0.5 to 2%, the amount of palladium present is at least 0.5%, the promoter is cobalt, mass ratio cobalt to palladium is from 20: 1 to 3: 1, the amount of substrate modifier present is from 3 to 90%.

Embodiment No. 195 is a hydrogenation catalyst of Embodiment No. 194, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium and zinc, as well as their precursors and mixtures of any of the above compounds.

Embodiment No. 196 is a hydrogenation catalyst of Embodiment No. 194, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of sodium, potassium, magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment No. 197 is a hydrogenation catalyst of Embodiment No. 194, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds.

Embodiment No. 198 is a hydrogenation catalyst of Embodiment No. 194, wherein the substrate modifier is selected from the group consisting of oxides and metasilicates of magnesium, calcium and zinc, as well as their precursors and mixtures of any of the above compounds.

Embodiment No. 199 is a hydrogenation catalyst of Embodiment No. 1984, wherein the substrate modifier is selected from the group consisting of calcium metasilicate, calcium metasilicate precursors, and mixtures of calcium metasilicate and its precursors.

An implementation option No. 200 is a hydrogenation catalyst containing: from 2.5 to 3.5 mass. percent platinum, from 3% of the mass. up to 5% of the mass. tin dispersed on fumed silica with a highly developed surface, the surface area of which is at least 200 m ² per gram, while said silica with a highly developed surface is promoted by calcium metasilicate in an amount of about 4% to 6%, the molar ratio of platinum to tin is from 4: 5 to 5: 4.

An implementation option No. 201 is a hydrogenation catalyst containing: from 0.5 to 2.5 mass. percent palladium, from 2% of the mass. up to 7% of the mass. rhenium, in this case, the mass ratio of rhenium to palladium is at least 1.5: 1.0, said rhenium and palladium are dispersed on a silica substrate, wherein said silica substrate contains at least 80% calcium metasilicate.

Embodiment No. 202 is a hydrogenation catalyst comprising catalytically active metals selected from the group consisting of: Fe, Co, Ni, Ru, Rh, Pd, Ir, Pt, Os, Ti, Zn, Cr, Mo and W in an amount from about 0.1% to about 10% by weight, on a stabilized modified oxide substrate, including basic non-volatile stabilizing modifiers in the form of oxides and metasilicates of alkaline earth metals, alkali metals, zinc, scandium, yttrium, precursors of these oxides and metasilicates, and their mixtures in quantities to neutralize the acid sites present on their surface, imparting resistance to shape changes (mainly due to, but not limited to, sintering, grain growth, grain boundary migration, migration of defects and dislocations, plastic deformation and / or other thermal changes in the microstructure) temperatures used in the hydrogenation of acetic acid; or both.

Embodiment No. 203 is a hydrogenation catalyst of Embodiment No. 202, wherein the amount and localization of the main stabilizer modifier are sufficient to reduce the number of acid sites present per square meter of the surface of the oxide substrate below the number of acid sites present per square meter of the surface of fumed silica having a degree of purity of at least about 99.7% of the mass.

Embodiment No. 204 is a hydrogenation catalyst of Embodiment No. 202, in which the amount and localization of the main stabilizer modifier are sufficient to reduce the number of acid centers present per square meter of the surface of the oxide substrate below the number of acid centers present per square meter of the surface of silicon dioxide Saint -Gobain NorPro HSA SS61138 having a degree of purity of at least about 99.7% of the mass.

Embodiment No. 205 is a hydrogenation catalyst of Embodiment No. 202, in which the amount and localization of the main stabilizer modifier are sufficient to reduce the number of acid sites present per square meter of the surface of the oxide substrate below half the number of acid sites present per square meter of the surface of pyrogenic dioxide silicon having a degree of purity of at least about 99.7% of the mass.

Embodiment No. 206 is a hydrogenation catalyst of Embodiment No. 202, wherein the amount and localization of the main stabilizer modifier are sufficient to reduce the number of acid sites present per square meter of the surface of the oxide substrate below half the number of acid sites present per square meter of the surface of silicon dioxide Saint-Gobain NorPro HSA SS61138, having a degree of purity of at least about 99.7% of the mass.

Embodiment No. 207 is a hydrogenation catalyst of Embodiment No. 202, in which the amount and localization of the main stabilizer modifier are sufficient to reduce the number of acid sites present per square meter of the surface of the oxide support below twenty-five percent of the number of acid sites present per square meter of surface pyrogenic silicon dioxide having a degree of purity of at least about 99.7% of the mass.

Embodiment No. 208 is a hydrogenation catalyst of Embodiment No. 202, wherein the amount and localization of the main stabilizer modifier are sufficient to reduce the number of acid sites present per square meter of the surface of the oxide support below twenty-five percent of the number of acid sites present per square meter of surface silica Saint-Gobain NorPro HSA SS61138 having a degree of purity of at least about 99.7% of the mass.

Embodiment No. 209 is a hydrogenation catalyst of Embodiment No. 202, in which the amount and localization of the main stabilizer modifier are sufficient to reduce the number of acid sites present per square meter of the surface of the oxide support below ten percent of the number of acid sites present per square meter of the pyrogenic surface silicon dioxide having a degree of purity of at least about 99.7% of the mass.

Embodiment No. 210 is a hydrogenation catalyst of Embodiment No. 220, in which the amount and localization of the main stabilizer modifier are sufficient to reduce the number of acid sites present per square meter of oxide surface below ten percent of the number of acid sites present per square meter of dioxide surface silicon Saint-Gobain NorPro HSA SS61138 having a degree of purity of at least about 99.7% of the mass.

In the above description of various embodiments of the invention, embodiments in which reference is made to other embodiments may be appropriately combined with other embodiments, as will be apparent to one skilled in the art.

Claims (12)

1. The method of producing ethanol by reducing acetic acid, comprising passing a gaseous stream containing hydrogen and acetic acid in the vapor phase with a molar ratio of hydrogen to acetic acid of at least about 4: 1, at a temperature of from about 225 ° C to 300 ° C above a hydrogenation catalyst containing platinum and tin dispersed on a modified substrate, wherein said modified substrate includes a substrate material and an effective amount of a substrate modifier selected from the group oyaschey metasilicates of alkaline earth metals, their precursors and their mixtures. 2. The method according to claim 1, in which the molar ratio of platinum to tin is from 1: 2 to 2: 1, preferably from 2: 3 to 3: 2. 3. The method according to PP. 1 and 2, in which the substrate material is a silica substrate. 4. The method according to PP. 1 and 2, in which the substrate material is selected from the group consisting of: silicon dioxide, iron oxide, aluminum oxide, titanium oxide, zirconium oxide, magnesium oxide, carbon, graphite, and mixtures thereof. 5. The method according to claim 1, in which the substrate modifier is selected from the group consisting of metasilicates of magnesium, calcium and zinc, as well as their precursors and mixtures of any of these compounds. 6. The method according to claim 1, in which:
(a) platinum is present in an amount of from 0.5% to 5% by weight of the catalyst; and
(b) tin is present in an amount of from 0.5 to 10%. 7. The method according to claim 1, wherein the surface area of the modified substrate is at least 100 m ² / g, preferably at least 200 m ² / g, most preferably at least 250 m ² / g. 8. The method according to claim 1, in which the modified substrate contains from 1 to 10 wt.% The modifier of the substrate. 9. The method according to claim 1, in which the amount of platinum is at least 0.75 wt.%, Preferably at least 1 wt.%. 10. The method according to claim 1, in which the method is carried out at a temperature of from 250 ° C to 300 ° C, and the modified substrate contains from 2.5 to 10 wt.% Calcium metasilicate. 11. The method according to claim 1, in which the catalyst occupies the volume of the reactor, and a gaseous stream containing hydrogen and acetic acid in the vapor phase is passed through the specified volume of the reactor with a space velocity of at least 1000 h ^-1 , preferably at least 2500 h ^-1 , most preferably at least 5000 h ^-1 . 12. The method according to claim 1, in which (i) at least 80%, preferably at least 90% of the converted acetic acid is converted to ethanol; (ii) less than 4%, preferably less than 2%, of acetic acid is converted to compounds other than compounds selected from the group consisting of ethanol, acetaldehyde, ethyl acetate, ethylene and mixtures thereof; and (iii) the activity of the catalyst decreases by less than 10% under the influence of a vaporous mixture of acetic acid and hydrogen at a molar ratio of 10: 1, at a pressure of 2 atm, a temperature of 275 ° C for a period of 336 hours or 500 hours.

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