EP2493606A2 - Catalyseurs pour fabriquer de l'éthanol à partir d'acide acétique - Google Patents

Catalyseurs pour fabriquer de l'éthanol à partir d'acide acétique

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Publication number
EP2493606A2
EP2493606A2 EP10702393A EP10702393A EP2493606A2 EP 2493606 A2 EP2493606 A2 EP 2493606A2 EP 10702393 A EP10702393 A EP 10702393A EP 10702393 A EP10702393 A EP 10702393A EP 2493606 A2 EP2493606 A2 EP 2493606A2
Authority
EP
European Patent Office
Prior art keywords
metal
catalyst
support
group
platinum
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP10702393A
Other languages
German (de)
English (en)
Inventor
Victor J. Johnston
Laiyuan Chen
Barbara F. Kimmich
Josefina T. Chapman
James H. Zink
Heiko Weiner
John L. Potts
Radmila Jevtic
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Celanese International Corp
Original Assignee
Celanese International Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US12/588,727 external-priority patent/US8309772B2/en
Application filed by Celanese International Corp filed Critical Celanese International Corp
Publication of EP2493606A2 publication Critical patent/EP2493606A2/fr
Withdrawn legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/002—Mixed oxides other than spinels, e.g. perovskite
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
    • B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/56—Platinum group metals
    • B01J23/62—Platinum group metals with gallium, indium, thallium, germanium, tin or lead
    • B01J23/622—Platinum group metals with gallium, indium, thallium, germanium, tin or lead with germanium, tin or lead
    • B01J23/626—Platinum group metals with gallium, indium, thallium, germanium, tin or lead with germanium, tin or lead with tin
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
    • B01J23/54—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/56—Platinum group metals
    • B01J23/64—Platinum group metals with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
    • B01J23/656—Manganese, technetium or rhenium
    • B01J23/6567—Rhenium
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/0201—Impregnation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/0201—Impregnation
    • B01J37/0207—Pretreatment of the support
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/08—Heat treatment
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C1/00—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon
    • C07C1/20—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon starting from organic compounds containing only oxygen atoms as heteroatoms
    • C07C1/24—Preparation of hydrocarbons from one or more compounds, none of them being a hydrocarbon starting from organic compounds containing only oxygen atoms as heteroatoms by elimination of water
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
    • C07C29/132—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group
    • C07C29/136—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH
    • C07C29/147—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH of carboxylic acids or derivatives thereof
    • C07C29/149—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by reduction of an oxygen containing functional group of >C=O containing groups, e.g. —COOH of carboxylic acids or derivatives thereof with hydrogen or hydrogen-containing gases
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
    • B01J21/16—Clays or other mineral silicates
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2523/00—Constitutive chemical elements of heterogeneous catalysts
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/50—Improvements relating to the production of bulk chemicals
    • Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts

Definitions

  • the present invention relates generally to catalysts for use in processes for
  • Vapor-phase acetic acid hydrogenation was studied further over a family of supported Pt-Fe catalysts in Rachmady, W.; Vannice, M. A. J Catal. (2002) Vol. 209, pg. 87-98) and Rachmady, W.; Vannice, M. A. J Catal. (2000) Vol. 192, pg. 322-334).
  • United States Patent No. 5,149,680 to Kitson et al. describes a process for the catalytic hydrogenation of carboxylic acids and their anhydrides to alcohols and/or esters utilizing platinum group metal alloy catalysts.
  • Bimetallic ruthenium-tin/silica catalysts have been prepared by reaction of tetrabutyl tin with ruthenium dioxide supported on silica. (Loessard et al, Studies in Surface Science and Catalysis (1989), Volume Date 1988, 48 (Struct. React. Surf), 591-600.)
  • Hindermann et al. (Hindermann et al, J. Chem. Res., Synopses (1980), (11), 373), disclosing catalytic reduction of acetic acid on iron and on alkali-promoted iron.
  • the present invention is directed to catalysts and processes for making catalysts that are suitable for use in processes for hydrogenating acetic acid to ethanol at high selectivities.
  • the invention relates to a catalyst comprising a first metal, a silicaceous support, at least one metasilicate support modifier, and optionally, a second metal.
  • the catalyst comprises a first metal, a second metal, a silicaceous support, and at least one support modifier.
  • the first metal may be selected from the group consisting of Group IB, IIB, IIIB, IVB, VB, VIB, VIIB, or VIII transitional metal, a lanthanide metal, an actinide metal or a metal from any of Groups IIIA, IV A, VA, or VIA.
  • the first metal may be selected from the group consisting of copper, iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium, platinum, titanium, zinc, chromium, rhenium, molybdenum, and tungsten
  • the second metal being selected from the group consisting of copper, molybdenum, tin, chromium, iron, cobalt, vanadium, tungsten, palladium, platinum, lanthanum, cerium, manganese, rhenium, and nickel.
  • the first metal may be present in an amount of from 0.1 to 25 wt.%, based on the total weight of the catalyst.
  • the second metal may be selected from the group consisting of copper, molybdenum, tin, chromium, iron, cobalt, vanadium, tungsten, palladium, platinum, lanthanum, cerium, manganese, ruthenium, rhenium, gold, and nickel.
  • the first metal may be present in an amount of from 0.1 to 10 wt.% and the second metal may be present in an amount of from 0.1 to 10 wt.%, based on the total weight of the catalyst.
  • the catalyst may comprise a third metal, which may be selected from the group consisting of cobalt, palladium, ruthenium, copper, zinc, platinum, tin, and rhenium and/or which may be present in an amount of 0.05 and 4 wt.%, based on the total weight of the catalyst.
  • the first metal is platinum and the second metal is tin having a molar ratio of platinum to tin being from 0.4:0.6 to 0.6:0.4.
  • the first metal is palladium and the second metal is rhenium having molar ratio of rhenium to palladium being from 0.7:0.3 to 0.85:0.15.
  • the catalysts may be suitable for use as a hydrogenation catalyst in converting acetic acid to ethanol and yields an acetic acid conversion of at least 10%.
  • the catalysts may have a selectivity to ethanol of at least 80% and/or a selectivity to methane, ethane, and carbon dioxide of less than 4%.
  • the catalyst has a productivity that decreases less than 6% per 100 hours of catalyst usage.
  • the silicaceous support may optionally be selected from the group consisting of silica, silica/alumina, calcium metasilicate, pyrogenic silica, high purity silica, and mixtures thereof and may be present in an amount of 25 wt.% to 99 wt.%, based on the total weight of the catalyst.
  • the silicaceous support has a surface area of from 50 m 2 /g to 600 m 2 /g.
  • the support modifier e.g., metasilicate support modifier, may optionally be selected from the group consisting of (i) alkaline earth metal metasilicates, (ii) alkali metal
  • the support modifier may be selected from metasilicates of a metal selected from the group consisting of sodium, potassium, magnesium, scandium, yttrium, and zinc, preferably being CaSi0 3 .
  • the support modifier may be present in an amount of 0.1 wt.% to 50 wt.%, based on the total weight of the catalyst.
  • the catalyst satisfies the formula:
  • the catalyst may satisfy the formula:
  • v and > are between 3:2 and 2:3; and/or (ii) w and x are between 1 :3 and 1 :5; and p and z and the relative locations of aluminum and calcium atoms present are controlled such that Bransted acid sites present upon the surface thereof are balanced by a support modifier; and p and q are selected such that p:q is from 1 :20 to 1 :200 with r being selected to satisfy valence requirements, and v and w are selected such that:
  • the invention also relates to processes for preparing catalysts.
  • a preferred embodiment relates to a process for preparing a catalyst, the process comprising the steps of (a) contacting a first metal precursor to a first metal with a modified silicaceous support to form an impregnated support, wherein the modified silicaceous support comprises a silicaceous material and at least one metasilicate support modifier; and (b) heating the impregnated support under conditions effective to reduce the first metal and form the catalyst.
  • the heating occurs under a reducing atmosphere, at least in part.
  • the process may further comprise the steps of (c) contacting the at least one metasilicate support modifier or a precursor thereof with the silicaceous material to form a modified support precursor; and (d) heating the modified support precursor under conditions effective to form the modified support, and also may further comprise calcining the catalyst.
  • the process further comprises the steps of impregnating and reducing a second metal precursor to a second metal different from the first metal on the support either before, after, or concurrently with steps (a) and (b).
  • the process further comprises the steps of impregnating and reducing a third metal precursor to a third metal different from the first metal and the second metal on the support either before, after, or concurrently with steps (a) and (b).
  • another embodiment of the invention relates to a process comprising the steps of (a) contacting a first metal precursor to a first metal with a modified silicaceous support comprising at least one support modifier, wherein the first metal is selected from the group consisting of copper, iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium, platinum, titanium, zinc, chromium, rhenium, molybdenum, and tungsten; (b) contacting a second metal precursor to a second metal, different from the first metal, with the modified silicaceous support, wherein the second metal is selected from the group consisting of copper, molybdenum, tin, chromium, iron, cobalt, vanadium, tungsten, palladium, platinum, lanthanum, cerium, manganese, rhenium, and nickel; and (c) heating the modified silicaceous support under conditions effective to reduce the first metal and the second
  • the heating occurs after steps (a) and (b).
  • the heating occurs (optionally under a reducing atmosphere, at least in part) between steps (a) and (b) to reduce the first metal and after steps (a) and (b) to reduce the second metal.
  • the process may further comprise the steps of (c) contacting the at least one metasilicate support modifier or a precursor thereof with the silicaceous material to form a modified support precursor; and (d) heating the modified support precursor under conditions effective to form the modified support, and also may further comprise calcining the catalyst. The calcining may occur after steps (a) and (b) or between steps (a) and (b).
  • the processes further comprise the steps of impregnating and reducing a third metal precursor to a third metal different from the first metal and the second metal on the support either before, after, or concurrently with steps (a) and (b).
  • the catalyst and components thereof e.g., the first metal, the second metal, the third metal (optional), the (silicaceous) support, and the
  • FIG. 1 A is a graph of the selectivity to ethanol and ethyl acetate using a Si0 2 -Pt m Sn 1-m catalyst
  • FIG. IB is a graph of the productivity to ethanol and ethyl acetate of the catalyst of FIG. 1A;
  • FIG. 1C is a graph of the conversion of the acetic acid of the catalyst of FIG. 1A;
  • FIG. 2A is a graph of the selectivity to ethanol and ethyl acetate using a Si0 2 -Re n Pd 1-n catalyst;
  • FIG. 2B is a graph of the productivity to ethanol and ethyl acetate of the catalyst of FIG. 2A;
  • FIG. 2C is a graph of the conversion of the acetic acid of the catalyst of FIG. 2A;
  • FIG. 3 A is a graph of the productivity of a catalyst to ethanol at 15 hours of testing
  • FIG. 3B is a graph of the selectivity of the catalyst of FIG. 3 A to ethanol
  • FIG. 4 A is a graph of the productivity of a catalyst to ethanol over 100 hours of testing according to another embodiment of the invention.
  • FIG. 4B is a graph of the selectivity of the catalyst of FIG. 4 A to ethanol
  • FIG. 5 A is a graph of productivity of a catalyst to ethanol over 20 hours of testing according to another embodiment of the invention.
  • FIG. 5B is a graph of the selectivity of the catalyst of FIG. 5 A to ethanol
  • FIG. 6 A is a graph of the conversion of the catalysts of Example 18.
  • FIG. 6B is a graph of the productivity of the catalysts of Example 18.
  • FIG. 6C is a graph of the selectivity at 250°C of the catalysts of Example 18.
  • FIG. 6D is a graph of the selectivity at 275°C of the catalysts of Example 18.
  • the present invention relates to catalysts for use in processes for producing ethanol by hydrogenating acetic acid in the presence of a catalyst.
  • the catalyst employed comprises at least one metal, a silicaceous support, and at least one support modifier, preferably a metasilicate support modifier.
  • the present invention also relates to processes for making these catalysts.
  • the catalysts of the present invention provide high selectivities to ethoxylates, such as ethanol and ethyl acetate, and in particular to ethanol, when employed in the hydrogenation of acetic acid.
  • ethoxylates such as ethanol and ethyl acetate
  • Embodiments of the present invention beneficially may be used in industrial applications to produce ethanol on an economically feasible scale.
  • the catalyst of the invention comprises a first metal and optionally one or more of a second metal, a third metal or additional metals on the support.
  • the numerical terms "first,” “second,” “third,” etc., when used to modify the word “metal,” are meant to indicate that the respective metals are different from one another.
  • the total weight of all supported metals present in the catalyst preferably is from 0.1 to 25 wt.%, e.g., from 0.1 to 15 wt.%, or from 0.1 wt.% to 10 wt.%.
  • weight percent is based on the total weight the catalyst including metal and support.
  • the metal(s) in the catalyst may be present in the form of one or more metal oxides. For purposes of determining the weight percent of the metal(s) in the catalyst, the weight of any oxygen that is bound to the metal is ignored.
  • the first metal may be a Group IB, IIB, IIIB, IVB, VB, VIB, VIIB, or VIII transitional metal, a lanthanide metal, an actinide metal or a metal from any of Groups IIIA, IV A, VA, or VIA.
  • the first metal is selected the group consisting of copper, iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium, platinum, titanium, zinc, chromium, rhenium, molybdenum, and tungsten.
  • the first metal is selected from the group consisting of platinum, palladium, cobalt, nickel, and ruthenium.
  • the first metal is selected from platinum and palladium.
  • the catalyst comprises platinum in an amount less than 5 wt.%, e.g., less than 3 wt.% or less than 1 wt.%, due to the availability of platinum.
  • the catalyst optionally further comprises a second metal, which typically would function as a promoter.
  • the second metal preferably is selected from the group consisting of copper, molybdenum, tin, chromium, iron, cobalt, vanadium, tungsten, palladium, platinum, lanthanum, cerium, manganese, ruthenium, rhenium, gold, and nickel. More preferably, the second metal is selected from the group consisting of copper, tin, cobalt, rhenium, and nickel. More preferably, the second metal is selected from tin and rhenium.
  • the catalyst includes two or more metals
  • one metal may act as a promoter metal and the other metal is the main metal.
  • platinum may be considered to be the main metal and tin may be considered the promoter metal.
  • the present specification refers to the first metal as the primary catalyst and the second metal (and optional metals) as the promoter(s). This should not be taken as an indication of the underlying mechanism of the catalytic activity.
  • the catalyst includes two or more metals, e.g., a first metal and a second metal
  • the first metal optionally is present in the catalyst in an amount from 0.1 to 10 wt.%, e.g., from 0.1 to 5 wt.%, or from 0.1 to 3 wt.%.
  • the second metal preferably is present in an amount from 0.1 and 20 wt.%, e.g., from 0.1 to 10 wt.%, or from 0.1 to 5 wt.%.
  • the two or more metals may be alloyed with one another or may comprise a non- alloyed metal solution or mixture.
  • the preferred metal ratios may vary somewhat depending on the metals used in the catalyst.
  • the mole ratio of the first metal to the second metal preferably is from 10:1 to 1:10, e.g., from 4:1 to 1 :4, from 2:1 to 1 :2, from 1.5:1 to 1 :1.5 or from 1.1:1 to 1:1.1. It has now surprisingly and unexpectedly been discovered that for platinum/tin catalysts, platinum to tin molar ratios on the order of from 0.4:0.6 to 0.6:0.4 (or about 1:1) are
  • FIGS. 1 A, IB and 1C particularly preferred in order to form ethanol from acetic acid at high selectivity, conversion and productivity, as shown in FIGS. 1 A, IB and 1C.
  • Selectivity to ethanol may be further improved by incorporating modified supports as described herein.
  • Molar ratios other than 1 : 1 may be preferred for catalysts comprising different metals.
  • rhenium/palladium catalysts for example, higher ethanol selectivities may be achieved at higher rhenium loadings than palladium loadings.
  • preferred rhenium to palladium molar ratios for forming ethanol in terms of selectivity, conversion and production are on the order of 0.7:0.3 to 0.85:0.15, or about 0.75:0.25 (3:1).
  • selectivity to ethanol may be further improved by incorporating modified supports as described herein.
  • the third metal may be selected from any of the metals listed above in connection with the first or second metal, so long as the third metal is different from the first and second metals.
  • the third metal is selected from the group consisting of cobalt, palladium, ruthenium, copper, zinc, platinum, tin, and rhenium. More preferably, the third metal is selected from cobalt, palladium, and ruthenium.
  • the total weight of the third metal preferably is from 0.05 and 4 wt.%, e.g., from 0.1 to 3 wt.%, or from 0.1 to 2 wt.%.
  • the catalyst comprises a first metal and no additional metals (no second metal, etc.).
  • the first metal preferably is present in an amount from 0.1 to 10 wt. %.
  • the catalyst comprises a combination of two or more metals on a support. Specific preferred metal compositions for various catalysts of this embodiment of the invention are provided below in Table 1. Where the catalyst comprises a first metal and a second metal, the first metal preferably is present in an amount from 0.1 to 5 wt.% and the second metal preferably is present in an amount from 0.1 to 5 wt.%.
  • the first metal preferably is present in an amount from 0.1 to 5 wt.%
  • the second metal preferably is present in an amount from 0.1 to 5 wt.%
  • the third metal preferably is present in an amount from 0.1 to 2 wt.%.
  • the first metal is platinum and is present in an amount from 0.1 to 5 wt.%
  • the second metal is present in an amount from 0.1 to 5 wt.%
  • the third metal if present, preferably is present in an amount from 0.05 to 2 wt.%.
  • the metals of the catalysts of the present invention may be dispersed throughout the support, coated on the outer surface of the support (egg shell) or decorated on the surface of the support.
  • the catalysts of the present invention further comprise a modified support, meaning a support that includes a support material and a support modifier, which adjusts the acidity of the support material.
  • the acid sites e.g. Brensted acid sites
  • the acidity of the support material may be adjusted by reducing the number or reducing the availability of Bransted acid sites on the support material.
  • the support material may also be adjusted by having the support modifier change the pKa of the support material. Unless the context indicates otherwise, the acidity of a surface or the number of acid sites thereupon may be determined by the technique described in F.
  • support materials are selected such that the catalyst system is suitably active, selective and robust under the process conditions employed for the formation of ethanol.
  • Suitable support materials may include, for example, stable metal oxide-based supports or ceramic-based supports.
  • Preferred supports include silicaceous supports, such as silica, silica/alumina, a Group IIA silicate such as calcium metasilicate, pyrogenic silica, high purity silica and mixtures thereof.
  • Other supports may be used in some embodiments of the present invention, including without limitation, iron oxide, alumina, titania, zirconia, magnesium oxide, carbon, graphite, high surface area graphitized carbon, activated carbons, and mixtures thereof.
  • the support comprises a basic support modifier having a low volatility or that is non- volatile.
  • Low volatility modifiers have a rate of loss that is low enough such that the acidity of the support modifier is not reversed during the life of the catalyst.
  • Such basic modifiers may be selected from the group consisting of: (i) alkaline earth oxides, (ii) alkali metal oxides, (iii) alkaline earth metal metasilicates, (iv) alkali metal metasilicates, (v) Group IIB metal oxides, (vi) Group IIB metal metasilicates, (vii) Group IIIB metal oxides, (viii) Group IIIB metal metasilicates, and mixtures thereof.
  • the support modifier is selected from the group consisting of oxides and metasilicates of any of sodium, potassium, magnesium, calcium, scandium, yttrium, and zinc, and mixtures of any of the foregoing.
  • the support modifier is a calcium silicate, more preferably calcium metasilicate (CaSi0 3 ). If the support modifier comprises calcium metasilicate, it is preferred that at least a portion of the calcium metasilicate is in crystalline form.
  • the total weight of the modified support which includes the support material and the support modifier, based on the total weight of the catalyst, preferably is from 75 wt.% to 99.9 wt.%, e.g., from 78 wt.% to 97 wt.%, or from 80 wt.% to 95 wt.%.
  • the support modifier preferably is provided in an amount sufficient to adjust the acidity, e.g., by reducing the number or reducing the availability of active Bransted acid sites, and more preferably to ensure that the surface of the support is substantially free of active Bransted acid sites.
  • the support modifier is present in an amount from 0.1 wt.% to 50 wt.%, e.g., from 0.2 wt.% to 25 wt.%, from 0.5 wt.% to 15 wt.%, or from 1 wt.% to 8 wt.%, based on the total weight of the catalyst.
  • the support material is present in an amount from 25 wt.% to 99 wt.%, e.g., from 30 wt.% to 97 wt.% or from 35 wt.% to 95 wt.%.
  • the support material is a silicaceous support material selected from the group consisting of silica, silica/alumina, a Group IIA silicate such as calcium metasilicate, pyrogenic silica, high purity silica and mixtures thereof.
  • silica is used as the silicaceous support, it is beneficial to ensure that the amount of aluminum, which is a common contaminant for silica, is low, preferably under 1 wt.%, e.g., under 0.5 wt.% or under 0.3 wt.%, based on the total weight of the modified support.
  • pyrogenic silica is preferred as it commonly is available in purities exceeding 99.7 wt.%.
  • High purity silica refers to silica in which acidic contaminants such as aluminum are present, if at all, at levels of less than 0.3 wt.%, e.g., less than 0.2 wt.% or less than 0.1 wt.%.
  • acidic contaminants such as aluminum
  • the aluminum content of such silica may be less than 10 wt.%, e.g., less than 5 wt.% or less than 3 wt.%.
  • the support comprises a support modifier in the range of from 2 wt.% to 10 wt.%
  • acidic impurities such as aluminum
  • the surface area of the silicaceous support material e.g., silica
  • the surface area of the silicaceous support material preferably is at least about 50 m 2 /g, e.g., at least about 100 m 2 /g, at least about 150 m 2 /g, at least about 200 m 2 /g or most preferably at least about 250 m 2 /g.
  • the silicaceous support material e.g., silica
  • the silicaceous support material e.g., silica
  • High surface area silica refers to silica having a surface area of at least about 250 m 2 /g.
  • silica having a surface area of at least about 250 m 2 /g.
  • surface area refers to BET nitrogen surface area, meaning the surface area as determined by ASTM D6556-04, the entirety of which is incorporated herein by reference.
  • the silicaceous support material also preferably has an average pore diameter of from 5 to 100 nm, e.g., from 5 to 30 nm, from 5 to 25 nm or from about 5 to 10 nm, as determined by mercury intrusion porosimetry, and an average pore volume of from 0.5 to 2.0 cm 3 /g, e.g., from 0.7 to 1.5 cm 3 /g or from about 0.8 to 1.3 cm 3 /g, as determined by mercury intrusion
  • the morphology of the support material, and hence of the resulting catalyst composition may vary widely.
  • the morphology of the support material and/or of the catalyst composition may be pellets, extrudates, spheres, spray dried microspheres, rings, pentarings, trilobes, quadrilobes, multi-lobal shapes, or flakes although cylindrical pellets are preferred.
  • the silicaceous support material has a morphology that allows for a packing density of from 0.1 to 1.0 g/cm 3 , e.g., from 0.2 to 0.9 g/cm 3 or from 0.5 to 0.8 g/cm 3 .
  • the silica support material preferably has an average particle size, e.g., meaning the diameter for spherical particles or equivalent spherical diameter for non-spherical particles, of from 0.01 to 1.0 cm, e.g., from 0.1 to 0.5 cm or from 0.2 to 0.4 cm. Since the one or more metal(s) that are disposed on or within the modified support are generally very small in size, they should not substantially impact the size of the overall catalyst particles. Thus, the above particle sizes generally apply to both the size of the modified supports as well as to the final catalyst particles.
  • a preferred silica support material is SS61138 High Surface Area (HSA) Silica Catalyst Carrier from Saint Gobain NorPro.
  • the Saint-Gobain NorPro SS61138 silica contains approximately 95 wt.% high surface area silica; a surface area of about 250 m 2 /g; a median pore diameter of about 12 ran; an average pore volume of about 1.0 cm 3 /g as measured by mercury intrusion porosimetry and a packing density of about 0.352 g/cm 3 (22 lb/ft 3 ).
  • a preferred silica/alumina support material is KA-160 (Sud Chemie) silica spheres having a nominal diameter of about 5 mm, a density of about 0.562 g/ml, in absorptivity of about 0.583 g H 2 0/g support, a surface area of about 160 to 175 m 2 /g, and a pore volume of about 0.68 ml/g.
  • the support preferably includes a support modifier that is effective to suppress production of ethyl acetate, rendering the catalyst composition highly selective to ethanol.
  • the catalyst composition preferably has a low selectivity toward conversion of acetic acid to ethyl acetate and highly undesirable by-products such as alkanes.
  • the acidity of the support preferably is controlled such that less than 4%, preferably less than 2% and most preferably less than about 1% of the acetic acid is converted to methane, ethane and carbon dioxide.
  • the acidity of the support may be controlled by using a pyrogenic silica or high purity silica as discussed above.
  • the modified support comprises a support material and calcium metasilicate as support modifier in an amount effective to balance Bransted acid sites resulting, for example, from residual alumina in the silica.
  • the calcium metasilicate is present in an amount from 1 wt.% to 10 wt.%, based on the total weight of the catalyst, in order to ensure that the support is essentially neutral or basic in character.
  • the support modifier e.g., calcium metasilicate
  • the support material e.g., silicaceous support material
  • the support material comprises a silicaceous support material that includes at least about 80 wt.%, e.g., at least about 85 wt.% or at least about 90 wt.%, high surface area silica in order to counteract this effect of including a support modifier.
  • the catalyst composition may be represented by the formula:
  • the catalyst may comprise (i) platinum and tin; (ii) palladium and rhenium; or (iii) platinum, tin, palladium and rhenium, p and q preferably are selected such that p:q is from 1 :20 to 1 :200 with r being selected to satisfy valence
  • the process conditions and values of v, w, x, y, p, q, and r are preferably chosen such that at least 70% of the acetic acid, e.g., at least 80% or at least 90%, that is converted is converted to a compound selected from the group consisting of ethanol and ethyl acetate while less than 4% of the acetic acid is converted to alkanes.
  • the process conditions and values of v, w, x, y, p, q, and r are preferably chosen such that at least 70% of the acetic acid, e.g., at least 80% or at least 90%, that is converted is converted to ethanol, while less than 4% of the acetic acid is converted to alkanes.
  • p is selected, in view of any minor impurities present, to ensure that the surface of the support is essentially free of active Bronsted acid sites.
  • composition of the catalyst comprises:
  • v saidy are between 3:2 and 2:3; and/or (ii) w and x are between 1 :3 and 1 :5.
  • p and z and the relative locations of aluminum and calcium atoms present preferably are controlled such that Bransted acid sites present upon the surface thereof are balanced by the support modifier, e.g., calcium metasilicate;
  • p and q are selected such that p:q is from 1 :20 to 1 :200 with r being selected to satisfy valence requirements and
  • v and w are selected such that:
  • the catalyst has a surface area of at least about 100 m /g, e.g., at least about 150 m 2 /g, at least about 200 m 2 /gor most preferably at least about 250 m 2 /g, and z and p > z.
  • p is selected, in view of any minor impurities present, to also ensure that the surface of the support is substantially free of active Bransted acid sites which seem to facilitate conversion of ethanol into ethyl acetate.
  • the process conditions and values of v, w, x, y, p, q, and r preferably are chosen such that at least 70% of the acetic acid, e.g., at least 80% or at least 90%, that is converted is converted to ethanol, while less than 4% of the acetic acid is converted to alkanes.
  • oxidic support materials for the catalysts of the present invention by incorporation of non-volatile support modifiers having either the effect of: counteracting acid sites present upon the support surface or the effect of thermally stabilizing the surface makes it possible to achieve desirable improvements in selectivity to ethanol, prolonged catalyst life, or both.
  • support modifiers based on oxides in their most stable valence state will have low vapor pressures and thus have low volatility or are rather non-volatile. Accordingly, it is preferred that the support modifiers are provided in amounts sufficient to: (i) counteract acidic sites present on the surface of the support material; (ii) impart resistance to shape change under hydrogenation
  • imparting resistance to shape change refers to imparting resistance, for example, to sintering, grain growth, grain boundary migration, migration of defects and dislocations, plastic deformation and/or other temperature induced changes in microstructure.
  • Catalysts of the present invention are particulate catalysts in the sense that, rather than being impregnated in a wash coat onto a monolithic carrier similar to automotive catalysts and diesel soot trap devices, the catalysts of the invention preferably are formed into particles, sometimes also referred to as beads or pellets, having any of a variety of shapes and the catalytic metals are provided to the reaction zone by placing a large number of these shaped catalysts in the reactor.
  • Commonly encountered shapes include extrudates of arbitrary cross- section taking the form of a generalized cylinder in the sense that the generators defining the surface of the extrudate are parallel lines.
  • any convenient particle shape including pellets, extrudates, spheres, spray dried microspheres, rings, pentarings, trilobes, quadrilobes and multi-lobal shapes may be used, although cylindrical pellets are preferred.
  • the shapes are chosen empirically based upon perceived ability to contact the vapor phase with the catalytic agents effectively.
  • catalysts of the present invention is the stability or activity of the catalyst for producing ethanol. Accordingly, it can be appreciated that the catalysts of the present invention are fully capable of being used in commercial scale industrial applications for hydrogenation of acetic acid, particularly in the production of ethanol. In particular, it is possible to achieve such a degree of stability such that catalyst activity will have rate of productivity decline that is less than 6% per 100 hours of catalyst usage, e.g., less than 3% per 100 hours or less than 1.5% per 100 hours. Preferably, the rate of productivity decline is determined once the catalyst has achieved steady-state conditions.
  • the catalyst activity may extend or stabilize, the productivity and selectivity of the catalyst for prolonged periods extending into over one week, over two weeks, and even months, of commercially viable operation in the presence of acetic acid vapor at temperatures of 125°C to 350°C at space velocities of greater than 2500 hr "1 .
  • the catalyst compositions of the invention preferably are formed through metal impregnation of the modified support, although other processes such as chemical vapor deposition may also be employed.
  • it typically is desired to form the modified support for example, through a step of impregnating the support material with the support modifier.
  • a precursor to the support modifier such as an acetate or a nitrate, may be used.
  • the support modifier e.g., CaSi0 3
  • the support material e.g., Si0 2 .
  • an aqueous suspension of the support modifier may be formed by adding the solid support modifier to deionized water, followed by the addition of colloidal support material thereto.
  • the resulting mixture may be stirred and added to additional support material using, for example, incipient wetness techniques in which the support modifier is added to a support material having the same pore volume as the volume of the support modifier solution. Capillary action then draws the support modifier into the pores in the support material.
  • the modified support can then be formed by drying and calcining to drive off water and any volatile components within the support modifier solution and depositing the support modifier on the support material. Drying may occur, for example, at a temperature of from 50°C to 300°C, e.g., from 100°C to 200°C or about 120°C, optionally for a period of from 1 to 24 hours, e.g., from 3 to 15 hours or from 6 to 12 hours.
  • the modified supports may be shaped into particles having the desired size distribution, e.g., to form particles having an average particle size in the range of from 0.2 to 0.4 cm.
  • the supports may be extruded, pelletized, tabletized, pressed, crushed or sieved to the desired size distribution. Any of the known methods to shape the support materials into desired size distribution can be employed. Calcining of the shaped modified support may occur, for example, at a temperature of from 250°C to 800°C, e.g., from 300 to 700°C or about 500°C, optionally for a period of from 1 to 12 hours, e.g., from 2 to 10 hours, from 4 to 8 hours or about 6 hours.
  • the metals are impregnated onto the modified support.
  • a precursor of the first metal preferably is used in the metal impregnation step, such as a water soluble compound or water dispersible
  • the second metal also preferably is impregnated into the modified support from a second metal precursor. If desired, a third metal or third metal precursor may also be impregnated into the modified support.
  • Impregnation occurs by adding, optionally drop wise, either or both the first metal precursor and/or the second metal precursor and/or additional metal precursors, preferably in suspension or solution, to the dry modified support.
  • the resulting mixture may then be heated, e.g., optionally under vacuum, in order to remove the solvent. Additional drying and calcining may then be performed, optionally with ramped heating to form the final catalyst composition.
  • the metal(s) of the metal precursor(s) preferably decompose into their elemental (or oxide) form.
  • the completion of removal of the liquid carrier may not take place until the catalyst is placed into use and calcined, e.g., subjected to the high temperatures encountered during operation.
  • the calcination step or at least during the initial phase of use of the catalyst, such compounds are converted into a catalytically active form of the metal or a catalytically active oxide thereof.
  • Impregnation of the first and second metals (and optional additional metals) into the modified support may occur simultaneously (co-impregnation) or sequentially.
  • the first and second metal precursors are mixed together and added to the modified support together, followed by drying and calcination to form the final catalyst composition.
  • a dispersion agent, surfactant, or solubilizing agent e.g., ammonium oxalate
  • the desired solvent e.g., water
  • the first metal precursor is first added to the modified support followed by drying and calcining, and the resulting material is then impregnated with the second metal precursor followed by an additional drying and calcining step to form the final catalyst composition.
  • Additional metal precursors e.g., a third metal precursor
  • a third metal precursor may be added either with the first and/or second metal precursor or an a separate third impregnation step, followed by drying and calcination.
  • combinations of sequential and simultaneous impregnation may be employed if desired.
  • Suitable metal precursors include, for example, metal halides, amine solubilized metal hydroxides, metal nitrates or metal oxalates.
  • suitable compounds for platinum precursors and palladium precursors include chloroplatinic acid, ammonium chloroplatinate, amine solubilized platinum hydroxide, platinum nitrate, platinum tetra ammonium nitrate, platinum chloride, platinum oxalate, palladium nitrate, palladium tetra ammonium nitrate, palladium chloride, palladium oxalate, sodium palladium chloride, and sodium platinum chloride.
  • the first metal precursor is not a metal halide and is substantially free of metal halides.
  • non-(metal halide) precursors are believed to increase selectivity to ethanol.
  • a particularly preferred precursor to platinum is platinum ammonium nitrate,
  • the "promoter" metal or metal precursor is first added to the modified support, followed by the "main” or “primary” metal or metal precursor.
  • exemplary precursors for promoter metals include metal halides, amine solubilized metal hydroxides, metal nitrates or metal oxalates.
  • each impregnation step preferably is followed by drying and calcination.
  • a sequential impregnation may be used, starting with the addition of the promoter metal followed by a second impregnation step involving co-impregnation of the two principal metals, e.g., Pt and Sn.
  • PtSn/CaSi0 3 on Si0 2 may be prepared by a first impregnation of CaSi0 3 onto the Si0 2 , followed by the co-impregnation with Pt(NH 3 ) (N04) 2 and Sn(AcO) 2 .
  • each impregnation step may be followed by drying and calcination steps.
  • the impregnation may be carried out using metal nitrate solutions.
  • various other soluble salts, which upon calcination release metal ions can also be used.
  • suitable metal salts for impregnation include, metal acids, such as perrhenic acid solution, metal oxalates, and the like. In those cases where substantially pure ethanol is to be produced, it is generally preferable to avoid the use of halogenated precursors for the platinum group metals, using the nitrogenous amine and or nitrate based precursors instead.
  • embodiment of the invention may be conducted in a variety of configurations using a fixed bed reactor or a fluidized bed reactor as one of skill in the art will readily appreciate.
  • an "adiabatic" reactor can be used; that is, there is little or no need for internal plumbing through the reaction zone to add or remove heat.
  • a shell and tube reactor provided with a heat transfer medium can be used.
  • the reaction zone may be housed in a single vessel or in a series of vessels with heat exchangers therebetween. It is considered significant that acetic acid reduction processes using the catalysts of the present invention may be carried out in adiabatic reactors as this reactor configuration is typically far less capital intensive than tube and shell configurations.
  • the catalyst is employed in a fixed bed reactor, e.g., in the shape of an elongated pipe or tube where the reactants, typically in the vapor form, are passed over or through the catalyst.
  • a fixed bed reactor e.g., in the shape of an elongated pipe or tube where the reactants, typically in the vapor form, are passed over or through the catalyst.
  • Other reactors such as fluid or ebullient bed reactors, can be employed, if desired.
  • the hydrogenation catalysts may be used in conjunction with an inert material to regulate the pressure drop of the reactant stream through the catalyst bed and the contact time of the reactant compounds with the catalyst particles.
  • the hydrogenation reaction may be carried out in either the liquid phase or vapor phase.
  • the reaction is carried out in the vapor phase under the following conditions.
  • the reaction temperature may the range from of 125°C to 350°C, e.g., from 200°C to 325°C, from 225°C to about 300°C, or from 250°C to about 300°C.
  • the pressure may range from 10 KPa to 3000 KPa (about 0.1 to 30 atmospheres), e.g., from 50 KPa to 2300 KPa, or from 100 KPa to 1500 KPa.
  • the reactants may be fed to the reactor at a gas hourly space velocities (GHSV) of greater than 500 hr "1 , e.g., greater than 1000 hr “1 , greater than 2500 hr “1 and even greater than 5000 hr “1 .
  • GHSV gas hourly space velocities
  • the GHSV may range from 50 hr “1 to 50,000 hr “1 , e.g., from 500 hr "1 to 30,000 hr “1 , from 1000 hr “1 to 10,000 hr "1 , or from 1000 hr "1 to 6500 hr "1 .
  • the hydrogenation optionally is carried out at a pressure just sufficient to overcome the pressure drop across the catalytic bed at the GHSV selected, although there is no bar to the use of higher pressures, it being understood that considerable pressure drop through the reactor bed may be experienced at high space velocities, e.g., 5000 hr "1 or 6,500 hr "1 .
  • the reaction consumes two moles of hydrogen per mole of acetic acid to produce one mole of ethanol
  • the actual molar ratio of hydrogen to acetic acid in the feed stream may vary from about 100:1 to 1:100, e.g., from 50:1 to 1 :50, from 20:1 to 1:2, or from 12:1 to 1 :1.
  • the molar ratio of hydrogen to acetic acid is greater than 4:1, e.g., greater than 5:1 or greater than 10:1.
  • Contact or residence time can also vary widely, depending upon such variables as amount of acetic acid, catalyst, reactor, temperature and pressure. Typical contact times range from a fraction of a second to more than several hours when a catalyst system other than a fixed bed is used, with preferred contact times, at least for vapor phase reactions, from 0.1 to 100 seconds, e.g., from 0.3 to 80 seconds or from 0.4 to 30 seconds.
  • the acetic acid may be vaporized at the reaction temperature, and then the vaporized acetic acid can be fed along with hydrogen in undiluted state or diluted with a relatively inert carrier gas, such as nitrogen, argon, helium, carbon dioxide and the like.
  • a relatively inert carrier gas such as nitrogen, argon, helium, carbon dioxide and the like.
  • the temperature should be controlled in the system such that it does not fall below the dew point of acetic acid.
  • conversion refers to the amount of acetic acid in the feed that is convert to a compound other than acetic acid. Conversion is expressed as a mole percentage based on acetic acid in the feed.
  • conversion of acetic acid is calculated from gas chromatography (GC) data using the following equation:
  • the conversion may be at least 10%, e.g., at least 20%, at least 40%, at least 50%, at least 60%, at least 70% or at least 80%.
  • catalysts that have high conversions are desirable, such as at least 80% or at least 90%, a low conversion may be acceptable at high selectivity for ethanol. It is, of course, well understood that in many cases, it is possible to compensate for conversion by appropriate recycle streams or use of larger reactors, but it is more difficult to compensate for poor selectivity.
  • Selectivity is expressed as a mole percent based on converted acetic acid. It should be understood that each compound converted from acetic acid has an independent selectivity and that selectivity is independent from conversion. For example, if 50 mole % of the converted acetic acid is converted to ethanol, we refer to the ethanol selectivity as 50%.
  • Total mmol C refers to total mmols of carbon from all of the products analyzed by gas chromatograph.
  • the selectivity to ethoxylates of the catalyst is at least 60%, e.g., at least 70%, or at least 80%).
  • the term "ethoxylates" refers specifically to the compounds ethanol, acetaldehyde, and ethyl acetate.
  • the selectivity to ethanol is at least 80%, e.g., at least 85% or at least 88%.
  • the selectivity to ethanol is at least 80%, e.g., at least 85% or at least 88%.
  • the selectivity to ethanol is at least 80%, e.g., at least 85% or at least 88%.
  • the selectivity to ethanol is at least 80%, e.g., at least 85% or at least 88%.
  • the selectivity to undesirable products is less than 4%, e.g., less than 2% or less than 1%.
  • alkanes are low, usually under 2%, often under 1%, and in many cases under 0.5% of the acetic acid passed over the catalyst is converted to alkanes, which have little value other than as fuel.
  • Productivity refers to the grams of a specified product, e.g., ethanol, formed during the hydrogenation based on the kilogram of catalyst used per hour.
  • a productivity of at least 200 grams of ethanol per kilogram catalyst per hour e.g., at least 400 grams of ethanol or least 600 grams of ethanol, is preferred.
  • the productivity preferably is from 200 to 3,000 grams of ethanol per kilogram catalyst per hour, e.g., from 400 to 2,500 or from 600 to 2,000.
  • Some catalysts of the present invention may achieve a conversion of acetic acid of at least 10%, a selectivity to ethanol of at least 80%, and a productivity of at least 200 g of ethanol per kg of catalyst per hour.
  • a subset of catalysts of the invention may achieve a conversion of acetic acid of at least 50%, a selectivity to ethanol of at least 80%, a selectivity to undesirable compounds of less than 4%, and a productivity of at least 600 g of ethanol per kg of catalyst per hour.
  • the crude ethanol product comprises ethanol in an amount from 15 wt.% to 70 wt.%, e.g., from 20 wt.% to 50 wt.%, or from 25 wt.% to 50 wt.%, based on the total weight of the crude ethanol product.
  • the crude ethanol product contains at least 22 wt.% ethanol, at least 28 wt.% ethanol or at least 44 wt.% ethanol.
  • the crude ethanol product typically will further comprise unreacted acetic acid, depending on conversion, for example, in an amount from 0 to 80 wt.%, e.g., from 5 to 80 wt.%, from 20 to 70 wt.%, from 28 to 70 wt.% or from 44 to 65 wt.%. Since water is formed in the reaction process, water will also be present in the crude ethanol product, for example, in amounts ranging from 5 to 30 wt.%, e.g., from 10 to 30 wt.% or from 10 to 26 wt.%.
  • the crude ethanol product is formed over a platinum/tin catalyst on a modified silica support, e.g., modified with CaSi0 3 .
  • a modified silica support e.g., modified with CaSi0 3 .
  • the crude ethanol product may have any of the compositions indicated below in Table 3.
  • the raw materials used in the hydrogenation process may be derived from any suitable source including natural gas, petroleum, coal, biomass and so forth. It is well known to produce acetic acid through methanol carbonylation, acetaldehyde oxidation, ethylene oxidation, oxidative fermentation, and anaerobic fermentation. As petroleum and natural gas prices fluctuate becoming either more or less expensive, methods for producing acetic acid and intermediates such as methanol and carbon monoxide from alternate carbon sources have drawn increasing interest. In particular, when petroleum is relatively expensive compared to natural gas, it may become advantageous to produce acetic acid from synthesis gas (“syn gas”) that is derived from any available carbon source.
  • Syn gas synthesis gas
  • United States Patent No. RE 35,377 to Steinberg et al. also incorporated herein by reference, provides a method for the production of methanol by conversion of carbonaceous materials such as oil, coal, natural gas and biomass materials.
  • the process includes
  • acetic acid in vapor form may be taken directly as crude product from the flash vessel of a methanol carbonylation unit of the class described in United States Patent No. 6,657,078 to Scates et al., the entirety of which is incorporated herein by reference.
  • the crude vapor product may be fed directly to the ethanol synthesis reaction zones of the present invention without the need for condensing the acetic acid and light ends or removing water, saving overall processing costs.
  • Ethanol obtained from hydrogenation processes using the catalysts of the invention may be used in its own right as a fuel or subsequently converted to ethylene which is an important commodity feedstock as it can be converted to polyethylene, vinyl acetate and/or ethyl acetate or any of a wide variety of other chemical products.
  • ethylene can also be converted to numerous polymer and monomer products. The dehydration of ethanol to ethylene is shown below.
  • dehydration catalysts can be employed in to dehydrate ethanol, such as those described in copending applications U.S. Application No. 12/221,137 and U.S.
  • a zeolite catalyst for example, may be employed as the dehydration catalyst. While any zeolite having a pore diameter of at least about 0.6 nm can be used, preferred zeolites include dehydration catalysts selected from the group consisting of mordenites, ZSM-5, a zeolite X and a zeolite Y. Zeolite X is described, for example, in U.S. Pat. No. 2,882,244 and zeolite Y in U.S. Pat. No. 3,130,007, the entireties of which are hereby incorporated by reference.
  • Ethanol may also be used as a fuel, in pharmaceutical products, cleansers, sanitizers, hydrogenation transport or consumption. Ethanol may also be used as a source material for making ethyl acetate, aldehydes, and higher alcohols, especially butanol. In addition, any ester, such as ethyl acetate, formed during the process of making ethanol according to the present invention may be further reacted with an acid catalyst to form additional ethanol as well as acetic acid, which may be recycled to the hydrogenation process.
  • the catalyst supports were dried at 120°C overnight under circulating air prior to use. All commercial supports (i.e., Si0 2 , Zr0 2 ) were used as a 14/30 mesh, or in its original shape (1/16 inch or 1/8 inch pellets) unless mentioned otherwise. Powdered materials (i.e., CaSi0 3 ) were pelletized, crushed and sieved after the metals had been added. The individual catalyst preparations are described in detail below.
  • the catalyst was prepared by first adding CaSi0 3 (Aldrich) to the Si0 2 catalyst support, followed by the addition of Pt/Sn.
  • an aqueous suspension of CaSi0 3 ( ⁇ 200 mesh) was prepared by adding 0.52 g of the solid to 13 ml of deionized H 2 0, followed by the addition of 1.0 ml of colloidal Si0 2 (15 wt.% solution, NALCO).
  • the suspension was stirred for 2 hours at room temperature and then added to 10.0 g of Si0 2 catalyst support (14/30 mesh) using incipient wetness technique. After standing for 2 hours, the material was evaporated to dryness, followed by drying at 120°C overnight under circulating air and calcination at 500°C for 6 hours. All of the Si0 2 -CaSi0 3 material was then used for Pt/Sn metal impregnation.
  • the catalysts were prepared by first adding Sn(OAc) 2 (tin acetate, Sn(OAc) 2 from Aldrich) (0.4104 g, 1.73 mmol) to a vial containing 6.75 ml of 1:1 diluted glacial acetic acid (Fisher). The mixture was stirred for 15 min at room temperature, and then, 0.6711 g (1.73 mmol) of solid Pt(NH 3 )4(N0 3 ) 2 (Aldrich) were added. The mixture was stirred for another 15 min at room temperature, and then added drop wise to 5.0 g of Si0 2 -CaSi0 3 support, in a 100 ml round-bottomed flask.
  • the metal solution was stirred continuously until all of the Pt/Sn mixture had been added to the Si0 2 -CaSi0 3 support while rotating the flask after every addition of metal solution.
  • the flask containing the impregnated catalyst was left standing at room temperature for two hours.
  • the flask was then attached to a rotor evaporator (bath temperature 80°C), and evacuated until dried while slowly rotating the flask.
  • the material was then dried further overnight at 120°C, and then calcined using the following temperature program: 25-» 160°C/ramp 5.0 deg/min; hold for 2.0 hours; 160— > 500°C/ramp 2.0 deg/min; hold for 4 hours. Yield: 11.21 g of dark grey material.
  • the material was prepared by first adding CaSi0 3 to the KA160 catalyst support (SiO 2 -(0.05) A1 2 0 3 , Sud Chemie, 14/30 mesh), followed by the addition of Pt/Sn.
  • an aqueous suspension of CaSi0 3 ( ⁇ 200 mesh) was prepared by adding 0.42 g of the solid to 3.85 ml of deionized H 2 0, followed by the addition of 0.8 ml of colloidal Si0 2 (15 wt.% solution, NALCO). The suspension was stirred for 2 hours at room temperature and then added to 5.0 g of KA160 catalyst support (14/30 mesh) using incipient wetness technique.
  • the catalysts were prepared by first adding Sn(OAc) 2 (tin acetate, Sn(OAc) 2 from Aldrich) (0.2040 g, 0.86 mmol) to a vial containing 6.75 ml of 1:1 diluted glacial acetic acid (Fisher). The mixture was stirred for 15 min at room temperature, and then, 0.3350 g (0.86 mmol) of solid Pt(NH 3 ) 4 (N0 3 ) 2 (Aldrich) were added. The mixture was stirred for another 15 min at room temperature, and then added drop wise to 5.0 g of Si0 2 -CaSi0 3 support, in a 100 ml round-bottomed flask.
  • the flask containing the impregnated catalyst was left standing at room temperature for two hours.
  • the flask was then attached to a rotor evaporator (bath temperature 80°C), and evacuated until dried while slowly rotating the flask.
  • the material was then dried further overnight at 120°C, and then calcined using the following temperature program: 25-»160°C/ramp 5.0 deg/min; hold for 2.0 hours; 160-»500°C/ramp 2.0 deg/min; hold for 4 hours. Yield: 5.19 g of tan-colored material.
  • This catalyst was prepared in the same manner as Example 1, with the following starting materials: 0.26 g of CaSi0 3 as a support modifier; 0.5 ml of colloidal Si0 2 (15 wt.% solution, NALCO), 0.3355 g (0.86 mmol) of Pt(NH 3 ) 4 (N0 3 ) 2 ; and 0.2052 g (0.86 mmol) of Sn(OAc) 2 . Yield: 10.90 g of dark grey material.
  • This catalyst was prepared in the same manner as Example 1, with the following starting materials: 0.69 g of Mg(AcO) as a support modifier; 1.3 g of colloidal Si0 2 (15 wt.% solution, NALCO), 0.2680 g (0.86 mmol) of Pt(NH 3 ) 4 (N0 3 ) 2 ; and 0.1640 g (0.86 mmol) of Sn(OAc) 2 . Yield: 8.35 g.
  • the Si0 2 support was impregnated with a solution of Mg(AcO) and colloidal Si0 2 . The support was dried and then calcined to 700°C.
  • the Si0 2 -CaSi0 3 (5) modified catalyst support was prepared as described in Example 1.
  • the Re/Pd catalyst was prepared then by impregnating the Si02-CaSi0 3 (5) (1/16 inch extrudates) with an aqueous solution containing N3 ⁇ 4Re0 4 and Pd(N0 3 )2.
  • the metal solutions were prepared by first adding NH 4 Re0 4 (0.7237 g, 2.70 mmol) to a vial containing 12.0 ml of deionized H 2 0. The mixture was stirred for 15 min at room temperature, and 0.1756 g (0.76 mmol) of solid Pd(N0 3 ) 2 was then added.
  • Powdered and meshed high surface area silica NPSG SS61138 (100 g) of uniform particle size distribution of about 0.2 mm was dried at 120°C in a circulating air oven atmosphere overnight and then cooled to room temperature. To this was added a solution of zinc nitrate hexahydrate. The resulting slurry was dried in an oven gradually heated to 110°C (>2 hours, 10°C/min.) then calcined. To this was added a solution of platinum nitrate
  • Ti0 2 -CaSi0 3 (5)-Pt(3)-Sn(l .8) The material was prepared by first adding CaSi0 3 to the Ti0 2 catalyst (Anatase, 14/30 mesh) support, followed by the addition of Pt/Sn as described in Example 1. First, an aqueous suspension of CaSi0 3 ( ⁇ 200 mesh) was prepared by adding 0.52 g of the solid to 7.0 ml of deionized H 2 0, followed by the addition of 1.0 ml of colloidal Si0 2 (15 wt.% solution, NALCO). The suspension was stirred for 2 h at room temperature and then added to 10.0 g of Ti0 2 catalyst support (14/30 mesh) using incipient wetness technique.
  • KAl 60-Pt(3)-Sn(l .8) The material was prepared by incipient wetness impregnation of KA160 catalyst support (SiO 2 -(0.05) A1 2 0 3 , Sud Chemie, 14/30 mesh) as described in Example 16.
  • the metal solutions were prepared by first adding Sn(OAc) 2 (0.2040 g, 0.86 mmol) to a vial containing 4.75 ml of 1 :1 diluted glacial acetic acid. The mixture was stirred for 15 min at room temperature, and then, 0.3350 g (0.86 mmol) of solid Pt(NH 3 ) 4 (N0 3 ) 2 were added.
  • Powdered and meshed high surface area silica NPSG SS61138 (100 g) of uniform particle size distribution of about 0.2 mm was dried at 120°C in a circulating air oven atmosphere overnight and then cooled to room temperature.
  • a solution of tin acetate (Sn(OAc) 2 ) was added to the resulting slurry was dried in an oven gradually heated to 110°C (>2 hours, 10°C/min.) then calcined.
  • Si0 2 -Ti0 2 (l 0)-Pt(3)-Sn(l .8) The Ti0 2 -modified silica support 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 10.0 g of Si0 2 catalyst support (1/16 inch extrudates) in a 100 ml round- bottomed flask. The flask was left standing for two hours at room temperature, and then evacuated to dryness using a rotor evaporator (bath temperature 80°C).
  • a rotor evaporator bath temperature 80°C
  • SA 250 m /g, 1/16 inch extrudates
  • Example 14 Hvdrogenation of Acetic Acid over Catalysts from Examples 1-13 and Gas Chromatographic (GC Analysis of the Crude Ethanol Product
  • reaction feed liquid of acetic acid was evaporated and charged to the reactor along with hydrogen and helium as a carrier gas with an average combined gas hourly space velocity (GHSV), temperature, and pressure as indicated in Table 4.
  • GHSV gas hourly space velocity
  • the feed stream contained a mole ratio hydrogen to acetic acid as indicated in Table 4.
  • the analysis of the products was carried out by online GC.
  • the front channel was equipped with an FID and a CP-Sil 5 (20 m) + WaxFFap (5 m) column and was used to quantify: Acetaldehyde; Ethanol; Acetone; Methyl acetate; Vinyl acetate; Ethyl acetate; Acetic acid; Ethylene glycol diacetate; Ethylene glycol; Ethylidene diacetate; and Paraldehyde.
  • the middle channel was equipped with a TCD and Porabond Q column and was used to quantify: C0 2 ; ethylene; and ethane.
  • the back channel was equipped with a TCD and
  • Molsieve 5A column was used to quantify: Helium; Hydrogen; Nitrogen; Methane; and Carbon monoxide.
  • FIG. 3 A illustrates the selectivity
  • FIG. 3B illustrates the productivity of the catalysts as a function of time on-stream during the initial portion of the catalysts life. From the results of this example as reported in FIG. 3 A and FIG. 3B, it can be appreciated that it is possible to attain a selectivity of over 90% and productivity of over 500 g of ethanol per kilogram of catalyst per hour.
  • Catalyst Stability Si0 2 -CaSi0 3 (5)-Pt(3)-Sn(1.8).
  • the catalytic performance and initial stability of Si0 2 -CaSi0 3 (5)-Pt(3)-Sn(1.8) was evaluated at constant temperature (260°C) over 100 hrs of reaction time. Only small changes in catalyst performance and selectivity were observed over the 100 hrs of total reaction time. Acetaldehyde appeared to be the only side product, and its concentration ( ⁇ 3 wt.%) remained largely unchanged over the course of the experiment.
  • a summary of catalyst productivity and selectivity is provided in FIGS. 4A and 4B.
  • Example 16 The procedure of Example 16 was repeated at a temperature of about 250° C.
  • FIGS. 5A and 5B illustrate the productivity and selectivity of the catalysts as a function of time on- stream during the initial portion of the catalysts life. From the results of this example, as reported in FIGS. 5 A and 5B, it can be appreciated, that it is still possible to attain a selectivity activity of over 90% but with productivity of over 800 g of ethanol per kilogram of catalyst per hour at this temperature.
  • Example 18
  • the catalyst of Example 3 was prepared with different loadings of support modifier, CaSi0 3 , and produced the following catalysts: (i) SiO 2 -Pt(1.5)-Sn(0.9); (ii) Si0 2 -CaSi0 3 (2.5)- Pt(1.5)-Sn(0.9); (iii) SiO 2 -CaSiO 3 (5.0)-Pt(1.5)-Sn(0.9); (iv) SiO 2 -CaSiO 3 (7.5)-Pt(1.5)-Sn(0.9); and (v) SiO 2 -CaSiO 3 (10)-Pt(l .5)-Sn(0.9).
  • Each catalyst was used in hydrogenating acetic acid at 250°C and 275°C under similar conditions, i.e., 1400 bar (200 psig) and a 10:1 hydrogen to acetic acid molar feed ratio, (683 sccm/min of 3 ⁇ 4 to 0.183 g/min AcOH).
  • the conversion is shown in FIG. 6A, productivity in FIG. 6B, selectivity at 250°C in FIG. 6C and selectivity at 275°C in FIG. 6D.

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Abstract

La présente invention concerne des catalyseurs et des procédés pour former des catalyseurs pour utilisation dans l'hydrogénation d'acide acétique pour former de l'éthanol. Dans un mode de réalisation, le catalyseur comprend un premier métal, un support siliceux, et au moins un modifieur de support de métasilicate. De préférence, le premier métal est choisi dans le groupe constitué du cuivre, du fer, du cobalt, du nickel, du ruthénium, du rhodium, du palladium, de l'osmium, de l'iridium, du platine, du titane, du zinc, du chrome, du rhénium, du molybdène, et du tungstène. De plus, le catalyseur peut comprendre un deuxième métal de préférence choisi dans le groupe constitué du cuivre, du molybdène, de l'étain, du chrome, du fer, du cobalt, du vanadium, du tungstène, du palladium, du platine, du lanthane, du cérium, du manganèse, du ruthénium, du rhénium, de l'or, et du nickel.
EP10702393A 2009-10-26 2010-02-02 Catalyseurs pour fabriquer de l'éthanol à partir d'acide acétique Withdrawn EP2493606A2 (fr)

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US12/588,727 US8309772B2 (en) 2008-07-31 2009-10-26 Tunable catalyst gas phase hydrogenation of carboxylic acids
PCT/US2010/022950 WO2011056247A2 (fr) 2009-10-26 2010-02-02 Catalyseurs pour fabriquer de l'éthanol à partir d'acide acétique

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Publication number Priority date Publication date Assignee Title
US20130197278A1 (en) * 2012-01-27 2013-08-01 Celanese International Corporation Process For Manufacturing Ethanol Using A Metallic Catalyst Supported on Titania
CN102600842A (zh) * 2012-03-02 2012-07-25 山西盛驰科技有限公司 乙酸加氢制乙醇催化剂及其制备方法和应用
US8536383B1 (en) 2012-03-14 2013-09-17 Celanese International Corporation Rhodium/tin catalysts and processes for producing ethanol
CN104043484B (zh) * 2013-03-13 2016-10-12 中国石油天然气股份有限公司 一种醋酸催化加氢制备乙醇的催化剂及其制备和应用
CN103331167A (zh) * 2013-07-19 2013-10-02 新地能源工程技术有限公司 一种乙酸直接制备乙醇的催化剂及制备方法和应用
CN105258185A (zh) * 2015-11-14 2016-01-20 无锡清杨机械制造有限公司 一种带空气净化功能的抽油烟机
CN105646143B (zh) * 2016-02-23 2018-09-04 上海华谊（集团）公司 醋酸制乙醇联产乙酸乙酯的方法
CN106345512B (zh) * 2016-08-03 2019-03-05 江苏大学 一种二元合金催化剂及其制备方法和用途
CN108358752A (zh) * 2018-04-18 2018-08-03 肖锦 一种乙酸加氢制乙醇的方法
EP3852919A1 (fr) * 2018-09-17 2021-07-28 SABIC Global Technologies B.V. Catalyseurs pour la production d'alcools et d'éthers à partir de gaz de synthèse
WO2020061012A1 (fr) * 2018-09-19 2020-03-26 Sabic Global Technologies, B.V. Catalyseurs bimétalliques supportés sur des zéolites pour la conversion sélective de n-butane en éthane

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2882244A (en) 1953-12-24 1959-04-14 Union Carbide Corp Molecular sieve adsorbents
US3130007A (en) 1961-05-12 1964-04-21 Union Carbide Corp Crystalline zeolite y
GB8509530D0 (en) 1985-04-13 1985-05-15 Bp Chem Int Ltd Hydrogenation of carboxylic acids
GB8707595D0 (en) 1987-03-31 1987-05-07 British Petroleum Co Plc Chemical process
US5149680A (en) 1987-03-31 1992-09-22 The British Petroleum Company P.L.C. Platinum group metal alloy catalysts for hydrogenation of carboxylic acids and their anhydrides to alcohols and/or esters
US5137861A (en) * 1991-01-22 1992-08-11 Mobil Oil Corp. Catalyst comprising a hydrogenation metal and a delaminated layered silicate
US5821111A (en) 1994-03-31 1998-10-13 Bioengineering Resources, Inc. Bioconversion of waste biomass to useful products
USRE35377E (en) 1993-05-27 1996-11-12 Steinberg; Meyer Process and apparatus for the production of methanol from condensed carbonaceous material
US5977010A (en) * 1995-06-15 1999-11-02 Engelhard Corporation Shaped hydrogenation catalyst and processes for their preparation and use
US5945570A (en) * 1998-10-29 1999-08-31 Arhancet; Juan Pedro Catalyst and process for preparing 1,3-propanediol
US6232352B1 (en) 1999-11-01 2001-05-15 Acetex Limited Methanol plant retrofit for acetic acid manufacture
US6657078B2 (en) 2001-02-07 2003-12-02 Celanese International Corporation Low energy carbonylation process
US6685754B2 (en) 2001-03-06 2004-02-03 Alchemix Corporation Method for the production of hydrogen-containing gaseous mixtures
EP1277826A1 (fr) * 2001-07-18 2003-01-22 ATOFINA Research Procédé d'hydrogénation et de déhydrogénation et catalyseurs utilisés dans ces procédés
US7608744B1 (en) * 2008-07-31 2009-10-27 Celanese International Corporation Ethanol production from acetic acid utilizing a cobalt catalyst

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2011056247A2 *

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BR112012009792A2 (pt) 2016-10-18
AU2010315899A1 (en) 2012-05-17
MX2012004839A (es) 2012-05-29
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AU2010315899A2 (en) 2012-06-21
WO2011056247A3 (fr) 2011-10-27

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