RU2724109C1 - Method of producing acrylic acid, method for selective oxidation of carbon monoxide, catalyst for selective oxidation of carbon monoxide, method for production thereof - Google Patents

Abstract

FIELD: chemistry.SUBSTANCE: present invention relates to chemical industry, specifically to a catalyst for selective oxidation of carbon monoxide in the presence of a gas mixture comprising propylene, water vapour and propane, containing platinum group metal particles, deposited on porous carrier surface containing phase γ-AlOand boehmite phase in amount of less than 10 wt. %. Invention also relates to a method for selective oxidation of carbon monoxide by reacting a gaseous mixture comprising carbon monoxide, propylene, water vapour, propane in the presence of said catalyst, as well as a method of producing acrylic acid and a method of producing a catalyst.EFFECT: technical result consists in improvement of efficiency of method of producing acrylic acid, reduced production costs and high safety of said method.55 cl, 5 dwg, 10 tbl, 9 ex

Description

FIELD OF THE INVENTION

The present invention relates to the chemical industry, and in particular, to a method for producing acrylic acid by partial oxidation of propane using the stage of selective oxidation of carbon monoxide in the process of recycling unreacted propane and / or propylene, as well as to a catalyst for the selective oxidation of carbon monoxide, as well as to a method for producing such a catalyst.

State of the art

Acrylic acid is used, in particular, as a monomer in the preparation of polymers, including polyester resins.

One of the industrially applicable methods is a method for producing acrylic acid by heterogeneous catalytic partial direct oxidation of propane in accordance with which:

1) Gaseous streams are introduced into the first reaction zone, at least one of which contains propane, oxygen and water.

2) The propane introduced into the reaction zone is subjected to catalytic oxidation to obtain a mixture of products containing acrylic acid.

The specified method for producing acrylic acid from propane is known, for example, from patents EP0529853 B1 (02.28.1996), EP0603836 B1 (05.20.1998) and others. In this case, in most cases, the reaction gas, including propane, reaches only a partial conversion, even at elevated temperatures . In this regard, for the economical implementation of heterogeneous catalytic direct oxidation of propane to obtain at least one of the desired target products, it is important to ensure that the unreacted propane and / or propylene contained in the product gas mixture is returned to the reaction stage.

In the process of industrial production of acrylic acid at the stages of oxidation of hydrocarbons, a gas containing carbon monoxide is formed as a by-product of oxidation. The carbon monoxide content in the recycle gas is highly undesirable, as this contributes to excessive dilution of the reaction medium and, as a consequence, a decrease in the efficiency of acrylic acid production. In addition, the presence of carbon monoxide in the reaction mixture can lead to a decrease in catalyst activity. The accumulation of carbon monoxide can also contribute to the formation of explosive mixtures in the oxidation reactor. As a consequence, it is important to clean the recirculation gas from the carbon monoxide contained in it.

Methods for removing carbon monoxide from a recycle stream by fractional distillation are known in the art. According to the invention presented in US8431743 B2 (04.30.2013), in the first reaction step, propane is subjected to heterogeneously catalyzed dehydrogenation, whereby a product gas mixture 1 containing propane and propylene and other components are obtained. Then, from the product gas mixture 1 formed in the first reaction stage, if necessary, a partial amount of components contained therein other than propane and propylene, for example, such as hydrogen and carbon monoxide, is converted to other compounds other than propane and propylene. Then, from the product gas mixture 1 formed in the first reaction stage, if necessary, components other than propane and propylene contained therein, for example, such as hydrogen, carbon monoxide and water vapor, are separated.

Such separation of propane and propylene can be accomplished, for example, by absorption followed by desorption in a high boiling, hydrophobic organic solvent. The disadvantage of this method is that all compounds whose boiling point is lower than the boiling point of propane and propylene are removed from the recycle stream. Such compounds include oxygen, nitrogen, water, carbon dioxide, which act as diluents in the oxidation process.

Another option for removing unwanted carbon monoxide from the recycle gas is its oxidation to carbon dioxide, which is then, if necessary, removed by adsorption. It is important that in the process of said oxidation, propane and / or even more reactive propylene are not oxidized.

In the patent EP0495504 B1 (04/09/1997) in the process of producing methacrylic acid, the process of oxidizing carbon monoxide to carbon dioxide in the presence of isobutane is used on a catalyst containing noble metals (platinum, palladium, rhodium, ruthenium), copper, cobalt, nickel, magnesium, iron and their alloys or oxides on an inorganic substrate. The authors indicate that the low temperature of the oxidation of carbon monoxide does not lead to the oxidation of isobutane, however, the text does not mention the oxidation of more reactive alkenes, and the possibility of carrying out the process in the presence of water vapor.

In the article “Selectively combusting CO in the presence of propylene” [Chemical Engineering and processing: Process intensification 70, 2013, pp. 162–168] the authors disclose a method for the oxidation of carbon monoxide in the presence of propylene and propane in the process of obtaining acrylic acid. As a catalyst for the selective oxidation of carbon monoxide, a noble metal such as palladium, platinum, rhodium, ruthenium supported on an inorganic support is used. Selective oxidation is carried out in a fluidized bed reactor to ensure mixing of the solid and gas mixture, and thus uniform distribution of the temperature of the reactor. U.S. Patent Application US20130131380 A1 (05/23/2015) also conducts oxidation of carbon monoxide in a fluidized bed reactor in the presence of a noble metal catalyst. The recycle gas stream, according to examples of the invention, may contain up to 20 mol%. water, 50 mol%. propane and a small amount of propylene and acrolein (less than 1 mol% of each). However, the use of fluidized bed reactors complicates the hardware design of the process and sets the requirements for the abrasion resistance of the catalyst.

An urgent task is to develop an economical and simple method for producing acrylic acid suitable for industrial use by oxidizing propane, in which a recirculation mode is ensured. The difficulty in recirculating the gas stream is that in addition to the unreacted propane and propylene, the stream contains other oxidation products, including the by-produced carbon monoxide, the presence of which in the gas recirculation stream is highly undesirable.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a method for producing acrylic acid by oxidizing propane, comprising a gas stream recirculation step containing compounds such as propane and propylene, whereby carbon monoxide is preliminarily removed by oxidation thereof.

Another objective of the present invention is the provision of a method for the selective oxidation of carbon monoxide, which is formed as a by-product in the process of producing acrylic acid by oxidation of propane to carbon dioxide by means of a catalyst for the selective oxidation of carbon monoxide to carbon dioxide.

The technical result of the present invention is to increase the productivity of the method for producing acrylic acid, reduce production costs, increase the safety of this method. Also, the technical result consists in the implementation of the method of oxidation of carbon monoxide to carbon dioxide in a recycle gas stream with high conversion and selectivity for carbon dioxide, as well as in increasing the stability of the catalyst for the oxidation of carbon monoxide in the presence of water vapor.

The present invention includes the following aspects below.

According to one aspect, the invention relates to a catalyst for the selective oxidation of carbon monoxide in the presence of a gas mixture comprising propylene, water vapor and propane containing platinum group metal particles deposited on the surface of a porous carrier containing a γ – Al ₂ O ₃ phase and a boehmite phase.

According to one aspect, the invention relates to a catalyst for the selective oxidation of carbon monoxide, where platinum group metal particles are deposited on the outer surface of the porous support.

According to another aspect, the invention relates to a catalyst characterized by a specific surface area of 220 to 280 m ² / g, an average pore size of 7 to 14 nm and a pore volume of 0.6 to 0.9 cm ³ / g.

According to another aspect, the invention relates to a catalyst, where the gas mixture contains propylene in an amount of from 1 to 3 vol. %, and water vapor in an amount of from 20 to 45 vol. %

According to another aspect, the invention relates to a catalyst, where the platinum group metal is selected from: rhodium, ruthenium, platinum, and palladium and combinations thereof.

According to another aspect, the invention relates to a catalyst, where the platinum group metal is palladium, wherein the palladium content is from 0.5 to 3.0% by weight, preferably from 1.5 to 2.8% by weight, even more preferably from 2.0 to 2.4% of the mass.

According to another aspect, the invention relates to a catalyst, where the thickness of the palladium layer deposited on the surface of the porous carrier is from 10 to 250 μm, preferably from 50 to 150 μm.

According to another aspect, the invention relates to a catalyst, where the porous carrier is a granule with a shape selected from spherical, cylindrical, rings, and combinations thereof.

According to another aspect, the invention relates to a catalyst, where the content of boehmite phase is up to 10 wt.%, Preferably from 0.5 to 7.0% of the mass, preferably from 1.5 to 5.0% of the mass.

According to another aspect, the invention relates to a catalyst, wherein the specific surface area of the catalyst is from 240 to 270 m ² / g.

According to another aspect, the invention relates to a catalyst, wherein the pore volume of the catalyst is 0.7 to 0.8 cm ³ / g.

According to another aspect, the invention relates to a catalyst, wherein the micropore content of the catalyst, namely pore size less than 2 nm, is from 1 to 5%, preferably 1.5%.

According to another aspect, the invention relates to a catalyst for the selective oxidation of carbon monoxide in the presence of a gas mixture comprising propylene, water vapor and propane containing platinum group metal particles deposited on the surface of a porous carrier containing a γ – Al ₂ O ₃ phase and a boehmite phase characterized by at least the following main X-ray diffraction peaks: 14 º, 46 º, 67 º.

According to another aspect, the invention relates to a method for the selective oxidation of carbon monoxide, by reacting a gaseous mixture comprising carbon monoxide, propylene, water vapor, propane, in the presence of a catalyst for selective oxidation of carbon monoxide.

According to another aspect, the invention relates to a method in which the interaction of the gaseous mixture is carried out in a tubular reactor.

According to another aspect, the invention relates to a method where the gaseous mixture contains carbon monoxide in an amount of from 2 to 4% vol., Propylene in an amount of from 1 to 3% vol., Water vapor in an amount of from 20 to 45% vol.

According to another aspect, the invention relates to a method where the interaction of the gaseous mixture is carried out in a tubular reactor with a tube diameter in the range from 10 to 60 mm, preferably from 20 to 50 mm.

According to another aspect, the invention relates to a method where the catalyst is loaded into the reactor in layers alternating with layers of inert material, so that the inert material layer is 1.1–2 times larger than the catalyst layer.

According to another aspect, the invention relates to a method where the interaction of the gaseous mixture is carried out at a temperature of from 60 to 160 ° C, preferably from 80 to 140 ° C, more preferably from 80 to 120 ° C.

According to another aspect, the invention relates to a method where the interaction of the gaseous mixture is carried out at an overpressure in the reactor in the range from 0.1 to 0.5 bar, preferably from 0.1 to 0.3 bar.

According to another aspect, the invention relates to a method where the contact time of the catalyst with the gaseous mixture is from 0.5 to 10 s, preferably from 1 to 3 s.

According to another aspect, the invention relates to a method for producing acrylic acid by heterogeneous oxidation of propane, comprising the steps of:

a) a feed gas stream containing propane, water vapor and an oxidizing agent is fed to a reactor containing a catalyst for the selective oxidation of propane to acrylic acid, to obtain a gaseous mixture containing acrylic acid, unreacted propane and propylene, carbon oxides and other impurities,

b) the gaseous mixture obtained in step a) is fed to the separation step to separate acrylic acid and produce a gaseous mixture including propane, propylene, steam, and carbon oxides,

c) the gaseous mixture obtained in step b) is fed to a carbon monoxide selective oxidation reactor containing a carbon monoxide selective oxidation catalyst, where carbon monoxide is oxidized according to the carbon monoxide oxidation method described above,

d) a gaseous mixture exiting the carbon monoxide selective oxidation reactor is fed to a water separation and carbon dioxide purification step, and

e) the gaseous mixture enriched in propane and propylene after step d) is returned to step a).

According to another aspect, the invention relates to a method further comprising the step of: prior to feeding the feed gas stream to a reactor containing a catalyst for selective oxidation of propane to acrylic acid, said gas stream is fed to a reactor containing a catalyst for selective oxidation of propylene to acrolein.

According to another aspect, the invention relates to a method in which the gaseous mixture obtained in stage a) contains minor amounts of acrolein and acetic acid.

According to another aspect, the invention relates to a method in which the oxidizing agent comprises molecular oxygen in pure form or in admixture with inert gaseous diluents.

According to another aspect, the invention relates to a method in which the water vapor content is from 20 to 45% vol., Preferably from 20 to 35% vol., More preferably from 20 to 30% vol.

According to another aspect, the invention relates to a method in which the conversion of propane is from 5 mol.% To 30 mol.%, Preferably from 20 to 25 mol.%.

According to another aspect, the invention relates to a method in which the selective oxidation of propane to acrylic acid is carried out at a temperature of from 320 to 420 ° C.

According to another aspect, the invention relates to a method in which the selective oxidation of propane to acrylic acid is carried out at a pressure of from 0.5 to 5 bar, preferably from 1 to 3 bar.

According to another aspect, the invention relates to a process in which step a) is carried out in a single reactor.

According to another aspect, the invention relates to a process wherein step a) is carried out in two or more reactors connected in series.

According to another aspect, the invention relates to a method in which stage a) is carried out in two or more parallel reactors.

According to another aspect, the invention relates to a method where step a) is carried out in a tubular reactor.

According to another aspect, the invention relates to a method where a coolant is used in a tubular reactor, which is selected from molten salts, low-melting metals or diphenyl mixtures.

According to another aspect, the invention relates to a method where stage a) is carried out in the presence of a catalyst, the temperature of which exceeds the temperature of the coolant by 40-60 ° C.

According to another aspect, the invention relates to a method where the temperature of the coolant in the tubular reactor is from 260 to 310 ° C.

According to another aspect, the invention relates to a method for producing a catalyst for the selective oxidation of carbon monoxide, comprising the steps of:

a) provide a catalyst carrier containing gamma-alumina and a boehmite phase of up to 10%,

b) reducing the platinum group metal on the surface of the catalyst support by adding a reagent-reducing agent;

c) cooling the resulting mixture to room temperature, followed by isolation of the catalyst from the mixture;

d) drying the catalyst,

e) restore the resulting catalyst in a stream of hydrogen;

f) passivate the catalyst in an inert gas stream.

According to another aspect, the invention relates to a method where the platinum group metal is selected from: rhodium, ruthenium, platinum, palladium.

According to another aspect, the invention relates to a method where the platinum group metal is palladium.

According to another aspect, the invention relates to a method where the step of providing a catalyst carrier comprises the following sub-steps:

i) preparing an aqueous suspension of γ – Al ₂ O ₃

ii) add to the specified suspension of the main precipitant,

iii) add a precursor containing a platinum group metal, followed by stirring, heating the resulting mixture, and keeping it for a predetermined time.

According to another aspect, the invention relates to a method in which the main precipitant comprises potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, or combinations thereof.

According to another aspect, the invention relates to a method in which the pH of the medium is maintained at a constant level of approximately 9-11, preferably 10.

According to another aspect, the invention relates to a method in which a precursor containing a platinum group metal is a palladium-containing precursor, and includes compounds selected from H ₂ PdCl ₆ , [Pd (NH ₃ ) ₂ Cl ₂ ], Pd (NO ₃ ) _{2 ,} H ₂ PdCl ₄ .

According to another aspect, the invention relates to a method in which a precursor containing a platinum group metal is added dosed over a period of time from 10 to 30 minutes at a temperature of from 70 to 80 ° C.

According to another aspect, the invention relates to a method in which, after dosing a precursor containing a platinum group metal, the catalyst suspension is maintained for a period of time from 20 minutes to 60 minutes, at a temperature of from 70 to 100 ° C.

According to another aspect, the invention relates to a method in which the reducing agent includes a solution of a weak organic acid salt and a strong base.

According to another aspect, the invention relates to a method in which the reducing agent is selected from the group comprising sodium formate, ammonium acetate, ammonium formate, and ammonium oxalate.

According to another aspect, the invention relates to a method in which, after the isolation step, the catalyst is purified from chloride ions.

According to another aspect, the invention relates to a method in which the resulting catalyst is dried at temperatures from 40 to 150 ° C at atmospheric pressure and / or pressure significantly lower than atmospheric.

According to another aspect, the invention relates to a method in which the precursor is restored to a metallic state on the surface of the catalyst in a stream of hydrogen in a tube furnace for a period of time from 30 to 60 minutes at temperatures from 100 to 200 ° C, preferably from 120 to 180 ° C, more preferably from 140 to 160 ° C.

According to another aspect, the invention relates to a method in which the reduced catalyst is cooled in a stream of an inert gas selected from argon, nitrogen or helium.

According to another aspect, the invention relates to a method in which the molar ratio of reagents Pd: basic precipitant: reagent-reducing agent is maintained in the range of 1: (10–2) :( 4–1), most preferably 1: 4: 1.5.

According to another aspect, the invention relates to a method in which γ-Al ₂ O ₃ is converted into boehmite by selecting the conditions for carrying out stages i – iii to shift the thermodynamic equilibrium towards the formation of the boehmite phase.

According to another aspect, the invention relates to a method in which, for the thermodynamic equilibrium shift towards the formation of a boehmite phase from the γ – Al ₂ O ₃ phase, γ – AL ₂ O ₃ is maintained in the presence of water at a temperature of from 80 to 100 ° C. for a period time from 20 minutes to 60 minutes

According to another aspect, the invention relates to a method in which the content of the boehmite phase is from 0.5 to 7.0% of the mass, preferably from 1.5 to 5.0% of the mass.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 Installation diagram for the production of acrylic acid by propane oxidation.

FIG. 2 XRD spectrum of the catalyst obtained in example 1, with a boehmite phase content of from 1.5 to 5% of the mass.

FIG. 3 XRD spectrum of the catalyst obtained in example 2, with a boehmite phase content of more than 10% of the mass.

FIG. 4 XRD spectrum of the catalyst obtained in example 3, does not contain boehmite phase.

Figure 5 The structure of the catalyst in the form of granules in cross section.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

The process of oxidizing carbon monoxide to carbon dioxide, according to the invention, is complicated by the following factors:

a) the need for selective oxidation of carbon monoxide in the presence of propane and propylene,

b) the process at elevated temperatures in the presence of water vapor, which helps to reduce the activity and stability of the known catalysts for the oxidation of carbon monoxide.

Thus, to provide an effective method for the oxidation of carbon monoxide to carbon dioxide in the presence of a gas mixture containing propane, propylene, water vapor, and other unreacted gases, a catalyst with high selectivity for carbon monoxide, while characterized by high activity and stability at high temperatures in the presence of water vapor.

The inventors unexpectedly found that a catalyst containing platinum group metal particles as an active component, deposited as a thin layer on the outer surface of a porous support that contains γ – Al ₂ O ₃ and an additional boehmite phase, has excellent selectivity and increased stability at high temperatures in the presence of water vapor. Preferably, the platinum group metals are selected from rhodium, ruthenium, platinum and palladium. The most preferred metal is palladium.

The surface of the catalyst can be divided into external and internal. The outer surface is the "outer" surface of the catalyst layer. The inner surface is formed by pore walls, cracks, etc. An important feature of the catalyst according to the present invention is that the active component is deposited on the outer surface of the catalyst carrier, thereby forming a crust layer on the surface of the carrier.

In the case of a granular form of the catalyst, such a surface is an option II in FIG. 5.

Due to the fact that the process of oxidation of carbon monoxide proceeds in the gas phase, the localization of the active component on the outer surface of the catalyst avoids the reaction in its diffusion region, which is characterized by low selectivity due to heating of the catalyst. When the active component is localized in the catalyst volume, the reaction rate will be determined not by the rate of the oxidation reaction itself, but by the diffusion rate of the reagent into the catalyst volume. The occurrence of diffusion restrictions upon localization of the active component in the catalyst volume leads to a decrease in the productivity of the entire process. Diffusion of propylene into the pore space of the catalyst and an increase in contact time with the catalyst will increase the likelihood of an undesired oxidation of propylene.

It is preferable to use a catalyst in the oxidation of carbon monoxide in which the layer thickness of the particles of the platinum group metal, in particular palladium deposited on the outer surface of the porous alumina support, is from 10 to 250 μm, more preferably from 50 to 150 μm.

The amount of palladium is from 0.5 to 3.0 wt. -%, preferably from 1.5 to 2.8 wt. -%, more preferably from 2 to 2.4 wt. %

According to the invention, the process of oxidation of carbon monoxide occurs at elevated temperatures in the presence of water vapor, and therefore there is a need to ensure hydrothermal stability of the catalyst. To this end, it is preferable to use a catalyst carrier as a catalyst carrier consisting of γ – Al ₂ O ₃ and an additional phase, boehmite, which is a compound with the chemical formula AlO (OH). Boehmite is a phase state of aluminum oxide and is primarily characterized by orthorhombic symmetry. The transformation of γ – Al ₂ O ₃ into boehmite is carried out by changing the reaction conditions to shift the thermodynamic equilibrium to the formation of boehmite. The present inventors have unexpectedly discovered that the presence of boehmite phase in the structure of the support significantly enhances the stability of the catalyst in the presence of water vapor.

In the course of the oxidation of carbon monoxide in the presence of water vapor, a phase transition of boehmite to pseudoboehmite, which is hydrated boehmite, can occur. But the deposition of a metal of the platinum group, in particular, palladium on the catalyst surface, helps to stabilize the boehmite phase due to the interaction of palladium with its hydroxide groups, which, in turn, helps to prevent further boehmite hydration with the formation of pseudoboehmite and, as a result, to improve the stability of the catalyst under reaction conditions . The content of boehmite in the composition of the catalyst carrier is up to 10% of the mass. The preferred content of boehmite in the composition of the catalyst carrier is from 0.5 to 7 wt. -%, more preferably from 1.5 to 5% of the mass.

Thus, one of the advantages of the catalyst of the present invention is increased hydrothermal stability in the presence of water vapor. Increased hydrothermal stability helps to preserve the surface area, porosity and pore size of the catalyst upon contact of the catalyst with water vapor.

The catalyst according to the invention is characterized by a specific surface area of 220 to 280 m ² / g, preferably 240 to 270 m ² / g.

The pore volume of the carrier in the catalyst is from 0.6 to 0.9 cm ³ / g, preferably from 0.7 to 0.8 cm ³ / g. A pore volume of less than about 0.6 cm ³ / g leads to a deterioration in the transport properties of the pores of the carrier and an increase in intra-diffusion inhibition during the oxidation of carbon monoxide, which contributes to a low conversion of carbon monoxide during its oxidation to carbon dioxide. A pore volume of more than about 0.9 cm ³ / g leads to a significant increase in the fragility of the catalyst, which subsequently does not allow it to be used in flow-type reactors.

The average pore size of the carrier in the catalyst is from 7 to 14 nm. In pores smaller than about 7 nm, there is a slow diffusion of propylene molecules, which leads to the fact that propylene molecules are retained in the pore space and react with oxygen to form oxidation products. An increase in pore size of more than 14 nm is also undesirable, because in this case, there is a sharp decrease in the specific surface area of the carrier, which substantially complicates the preparation of a catalyst with the required distribution and dispersion of the active component.

The preferred micropore content in the catalyst support, namely pores less than 2 nm in size, is from 1 to 5% relative (rel.), Preferably 1.5% rel.

Thus, the catalyst used in the process of selective oxidation of carbon monoxide to carbon dioxide in the presence of a gas mixture comprising carbon monoxide in an amount of from 2 to 4% vol., Propylene in an amount of from 1 to 3% vol., Water vapor in an amount of from 20 up to 45% vol., unreacted gases, including propane - the rest, in accordance with the present invention, is characterized by the following parameters:

The active component of the catalyst is a platinum group metal, preferably palladium in an amount of from 0.5 to 3.0% by weight, preferably from 1.5 to 2.8% by weight, more preferably from 2.0 to 2.4% mass .;

a platinum group metal is deposited on the outer surface of the catalyst support with a thin layer from 10 to 250 microns thick, more preferably from 50 to 150 microns;

the catalyst carrier contains γ – Al ₂ O ₃ and an additional phase, boehmite, in an amount of from 0.5 to 7.0% by mass, more preferably from 1.5 to 5.0% by mass .;

the specific surface area of the catalyst is from 220 to 280 m ² / g, preferably from 240 to 270 m ² / g;

the pore volume of the catalyst carrier is from 0.6 to 0.9 cm ³ / g, preferably from 0.7 to 0.8 cm ³ / g;

the average pore size of the catalyst carrier is from 7 to 14 nm;

the micropore content of the catalyst carrier, namely pores less than 2 nm in size, is from 1 to 5%, preferably 1.5% rel. %

Thus, according to the present invention, the high efficiency of the catalyst, which consists in its stability in the presence of water vapor at elevated temperatures and the selectivity of the oxidation of carbon monoxide to carbon dioxide, is achieved due to the combination of the presented features, namely due to:

- creating the required phase state (boehmite) on the surface of the catalyst carrier layer of aluminum oxides;

- effective distribution of the active component in the form of a thin layer on the surface of the catalyst carrier;

- ensuring optimal specific surface area and porous structure of the catalyst.

The catalyst disclosed in the present invention can be obtained by a process that includes the following steps in which:

a) provide a catalyst carrier containing gamma-alumina and a boehmite phase of up to 10%,

b) reducing the platinum group metal on the surface of the catalyst support by adding a reagent-reducing agent;

c) cooling the resulting mixture to room temperature, followed by isolation of the catalyst from the mixture;

d) drying the catalyst.

e) restore the resulting catalyst in a stream of hydrogen;

f) passivate the catalyst in an inert gas stream.

Preferably, the step of providing the catalyst carrier comprises the following sub-steps:

1. Preparation of an aqueous suspension of γ – Al ₂ O ₃ ;

2. Adding a basic precipitant to the aqueous suspension of γ – Al ₂ O ₃ , which provides the creation of an alkaline medium with a pH of 9–11, preferably 10;

3. Batch addition of a precursor containing a platinum group metal, in particular palladium, followed by stirring, heating the resulting mixture and keeping it for a predetermined time.

At stages 2 and 3, the formation of boehmite phase in the composition of the catalyst carrier occurs.

As the main precipitant, providing the creation of an alkaline environment, can be used a compound selected from the group including: potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate and other alkaline agents. Preferred is the use of sodium carbonate. The use of sodium carbonate as the main precipitant allows the formation of a buffer solution that provides the creation of an alkaline medium with a constant pH ≈ 9–11, preferably equal to 10, which, in turn, avoids the need to control the pH during the entire preparation of the catalyst. A medium with a pH of about 9–11 is necessary for the formation of functional groups with a negative charge on the surface of the catalyst support, the presence of which contributes to better adsorption of platinum group metal anions from solution.

In a preferred embodiment, as a precursor containing a platinum group metal, a palladium-containing precursor is used, which can be used compounds selected from [Pd (NH ₃ ) ₂ Cl ₂ ], Pd (NO ₃ ) ₂ , preferably H ₂ PdCl ₄ . A palladium-containing precursor is added dosed over a period of time from 10 to 30 minutes at a temperature of from 70 to 80 ° C. After dosing the palladium-containing precursor, the catalyst suspension is maintained for a period of time from 20 minutes to 60 minutes, at a temperature of from 70 to 100 ° C.

In order to obtain dispersed palladium particles of a certain size (1-3 nm) on the surface of the catalyst, a reducing agent is added to the suspension, which is used as a solution of a salt of a weak organic acid and a strong base, for example, sodium formate, ammonium acetate, ammonium formate, ammonium oxalate. It is preferable to use sodium formate, which does not contain nitrogen, which adversely affects the activity of the catalyst.

After cooling the solution to room temperature, the catalyst is isolated by any method known in the art, for example, centrifugation, filtration, decantation.

After the separation stage, the catalyst is purified from chloride ions, the presence of which in the composition of the catalyst leads to a decrease in the adsorption of oxygen on its surface, which in turn leads to a decrease in the activity of the catalyst. Monitoring the completeness of removal of chloride ions is carried out using a qualitative reaction of the washing solution with silver nitrate.

The resulting catalyst is dried at temperatures from 40 to 150 ° C at atmospheric pressure and / or pressure much lower than atmospheric, for example, vacuum drying is carried out at 100-150 ° C.

The recovery of the active component to a metallic state on the surface of the catalyst is carried out in a stream of hydrogen in a tube furnace for a period of time from 30 to 60 minutes at temperatures from 100 to 200 ° C, preferably from 120 to 180 ° C, more preferably from 140 to 160 ° C . The recovered catalyst is then cooled in a stream of inert gas selected from argon, nitrogen or helium. It is preferable to use helium, in the atmosphere of which processes of formation of inactive surface paladium-containing structures do not proceed. During the preparation of the catalyst, the molar ratio of Pd: Na ₂ CO ₃ : HCOONa reagents is maintained in the range of 1: (10–2) :( 4–1), most preferably 1: 4: 1.5.

Another object of the present invention is a method for the selective oxidation of carbon monoxide to carbon dioxide in the presence of a gas mixture containing propane, propylene, steam using the above catalyst. The composition of the gas mixture includes carbon monoxide in an amount of from 2 to 4% vol., Propylene in an amount of from 1 to 3% vol., Water vapor in an amount of from 20 to 45% vol., Unreacted gases, including propane - the rest .

In the process of selective oxidation of carbon monoxide to carbon dioxide, there is a need to organize the efficient removal of a significant amount of heat released during the catalytic oxidation reaction in the gas phase, in which the gas mixture interacts with oxygen in the presence of a catalyst. Such an effective heat removal protects the catalyst from local overheating, and, as a consequence, from destruction and exceeding the temperature acceptable for the selective oxidation reaction.

Thus, according to the invention, in order to efficiently remove a large amount of reaction heat generated by a gas-phase catalytic oxidation reaction, the carbon monoxide oxidation process is carried out using a tubular reactor, in which tubes a fixed catalyst bed is loaded. It is preferable to use a tubular reactor with a tube diameter in the range from 10 to 60 mm, preferably from 20 to 50 mm. In the case of using tubes with a diameter of more than 50 mm, a local overheating of the catalyst layer occurs due to inefficient heat removal. When using tubes with a diameter of less than 20 mm, on the one hand, technical difficulties will arise with loading and unloading the catalyst, on the other hand, the hydrodynamic resistance of the catalyst layer will increase the flow of raw materials, this will lead to a pressure gradient along the length of the tube, which is undesirable for the process of direct oxidation of propane to acrylic acid.

In this case, in order to achieve maximum heat dissipation, the reactor tubes are arranged vertically, and the reaction mass is fed from top to bottom. As a coolant circulating in the reactor, solutions of monohydroxy alcohols, water and silicone oils can be used.

Also, to ensure efficient heat removal, the catalyst is loaded into the reactor in layers alternating with layers of inert material, so that the inert material layer is 1.1–2 times larger in volume than the catalyst layer. At the same time, glass, quartz and other heat-resistant materials that do not reduce the target reaction can be used as an inert material.

For carrying out the selective oxidation reaction of carbon monoxide, a catalyst can be used in the form of granules with a shape selected from spherical, cylindrical, rings, and combinations thereof.

The temperature of the selective CO oxidation reaction according to the invention is from 60 to 160 ° C, preferably from 80 to 140 ° C, more preferably from 80 to 120 ° C. Carrying out the reaction at a temperature of less than 60 ° C is not advisable due to the low conversion of carbon monoxide, at temperatures above 160 ° C - due to the high conversion of propylene.

A suitable overpressure in the reactor is in the range from 0.1 to 0.5 bar, preferably from 0.1 to 0.3 bar.

The contact time during the reaction is from 0.5 to 10 s, preferably from 1 to 3 s. Carrying out the reaction with a longer contact time is not economically feasible due to the need for a large catalyst load. With a shorter contact time, a heating of the catalyst layer is observed above 160 ° C, which contributes to the occurrence of undesired oxidation reactions of propylene and propane.

Another object of the present invention is a method for producing acrylic acid, which provides for the recirculation of a gas stream containing valuable unreacted components, such as propylene and propane, comprising the step of selectively oxidizing carbon monoxide to carbon dioxide, in accordance with which:

1. A feed gas stream containing propane, water vapor and an oxidizing agent is fed to a propane oxidation reactor in which a catalyst for selective oxidation of propane to acrylic acid is located at a temperature of from 320 to 420 ° C;

2. The gas mixture obtained at the outlet of the propane oxidation reactor containing acrylic acid, propane and propylene, carbon oxides, as well as optional minor amounts of acrolein and acetic acid, is fed to the stage of separation of liquid and gaseous products, followed by separation of acrylic acid;

3. The stream of gaseous products containing propane, propylene, water vapor, carbon oxides, is fed into the reactor for the selective oxidation of carbon monoxide in carbon dioxide at a temperature of from 80 to 100 ° C;

4. The gas mixture leaving the selective carbon monoxide reactor goes to the stage of water separation and carbon dioxide purification, after which the remaining gas mixture enriched in propane and propylene is recycled.

In a preferred embodiment of the invention, before the feed gas stream is introduced into the propane oxidation reactor, said gas stream is fed to the reactor in which the catalyst for selective oxidation of propylene to acrolein is located.

As the oxidizing agent, according to the invention, molecular oxygen is used, which can be added to the reaction gas mixture, for example, in pure form or in a mixture with gases, mainly inert.

Since the process of producing acrylic acid is accompanied by a large heat release, the hydrocarbon feed to the propane oxidation reactor is diluted with gas, which, due to its heat capacity, is capable of absorbing the heat released during the reaction. As such a gas, at least one gaseous inert diluent selected from N ₂ , H ₂ O, CO ₂ , He, Ar, saturated C ₁ –C ₅ hydrocarbons (for example, according to DE 924431 A1 and EP 293224 A) is used. etc.).

In order to remove heat and to conduct the reaction in accordance with the present invention, water vapor is used which absorbs the heat of reaction and decreases the temperature gradient across the catalyst bed. The heat capacity of water allows, on the one hand, to compensate for the temperature of the hot spots of the reactor, on the other hand, dilution with water vapor reduces the partial pressure of the initial and final product. The use of water vapor also helps to increase the service life of the catalyst for the oxidation of propane and reduce its coke formation. In addition, carrying out the process in the presence of water vapor ensures the safety of the entire process, since the composition of the gas mixture in this case is outside the explosive range.

The water vapor content according to the invention can be from 20 to 45% vol., Preferably from 20 to 35% vol., More preferably from 20 to 30% vol.

According to the present invention, it is advantageous to carry out a process in which propane conversion is achieved in the range from 5 mol% to 30 mol%, preferably from 20 to 25 mol%. This is due to the fact that the remaining amount of unreacted propane in the subsequent at least one oxidation zone mainly acts as a gaseous inert diluent and can later be returned to the oxidation zone without loss.

To realize the above conversion of propane, it is preferable to carry out its heterogeneous catalyzed oxidation at an operating pressure of from 0.5 to 5 bar, preferably from 1 to 3 bar.

The process of oxidation of propane in order to obtain acrylic acid is carried out at a temperature of from 320 to 420 ° C, preferably from 350 to 390 ° C in a reactor with a stationary catalyst bed. The flow rate of the mixture through the oxidation catalysts is from 1.6 to 2.2 m ³ / h, preferably from 1.8 to 2.2 m ³ / h.

In order to increase the yield of acrylic acid, the oxidation of propane can be carried out not in one reactor, but in two or more series or in parallel connected reactors.

According to the invention, the catalytic oxidation in the vapor phase is preferably carried out in a tubular reactor. Carrying out oxidation processes in tubular reactors allows the reaction temperature to be controlled by efficiently removing a significant amount of heat generated during the catalytic oxidation reaction in the vapor phase, in which the oxidizable substance is in contact with molecular oxygen in the presence of a solid catalyst. This method protects the catalyst from destruction resulting from local overheating of the catalytic layer (formation of hot spots).

The heat generated due to the oxidation reaction proceeding on the catalyst is transferred through the wall of the reactor tube to a boiling coolant, which is necessary to maintain a uniform temperature in the catalyst bed. The coolant vapor through the connecting pipe enters the return refrigerator, cooled by water. In the reflux condenser, the coolant vapors condense and by gravity return to the reactor. A nitrogen pad is created in the upper part of the return cooler with a continuous supply of nitrogen through an adjustable rotameter. The pressure of the nitrogen pad and, accordingly, the coolant vapor is regulated by a pressure regulator. Thus, the boiling point of the coolant is automatically controlled by setting the pressure. In order to avoid a temperature gradient in the coolant, the heating of the coolant condensate supply line is electrically heated, which ensures its boiling. The isothermality of the liquid coolant layer is controlled by thermocouples.

As a heat carrier, primarily liquid thermostatic media are used. It is preferable to use molten salts, such as potassium nitrate, potassium nitrite, sodium nitrite and / or sodium nitrate, or low-melting metals, as well as diphenyl mixtures, for example, consisting of a mixture of diphenyl and diphenyl ether (Dauterm or DOWTHERM).

The temperature of the coolant is from 260 to 310 ° C.

The maximum temperature in the catalyst bed exceeds the coolant temperature by 40–60 ° С.

Catalysts suitable for the heterogeneous catalytic gas-phase oxidation of propane to acrylic acid are metal oxide mixtures of the general formula MoV _a A _b B _c O _n in which Mo is molybdenum, V is vanadium, A _b is tellurium (Te) or antimony (Sb) , B _c is at least one element from the group comprising niobium (Nb), tantalum (Ta), tungsten (W), titanium (Ti), aluminum (Al), zirconium (Zr), chromium (Cr), manganese (Mn), gallium (Ga), iron (Fe), ruthenium (Ru), cobalt (Co), rhenium (Rh), nickel (Ni), palladium (Pd), platinum (Pt), lanthanum (La), bismuth (Bi), boron (B), cesium (Cs), tin (Sn), zinc (Zn), silicon (Si) and indium (In), O is oxygen.

Mixtures of metal oxides whose composition corresponds to the above formula are known in patent applications EP 0608838, EP 0529853, JP – A 7–232071, JP – A 10–57813, JP – A 2000–37632, JP – A 10–36311, WO 00/29105, in patents RU 2495720, RU 2285690.

To prevent the accumulation of high propylene content in the recycle (more than 5–10% vol.), As well as to increase the yield of acrylic acid, before the feed gas stream is introduced into the propane oxidation reaction zone, this gas stream is fed to the reactor in which the selective catalyst is located oxidation of propylene to acrolein.

In the reactor in which the oxidation of propylene to acrolein takes place, any propylene oxidation catalyst known in the art is used, containing metal oxides selected from bismuth (Bi), molybdenum (Mo), cobalt (Co), nickel (Ni), iron ( Fe), potassium (K), phosphorus (P), silicon (Si), etc. (SU1141627, RU2568636).

Of particular importance is the method according to the invention when it is used in recirculation mode. In this case, the target product is separated from the gas mixture leaving the propane oxidation reaction zone, and the remaining unreacted propane remaining in this gas mixture, as a rule, together with the unreacted propylene contained therein, is recycled to the oxidation stage, having previously removed from it the side-formed monoxide carbon according to the method of selectively removing carbon monoxide to carbon dioxide described in the present invention.

The gas recirculated to the reaction medium containing unreacted propane and propylene is introduced into the same place in the reaction zone into which other propane-containing gas streams are introduced, that is, as an integral part of the initial reaction gas mixture.

Below is a detailed description of Figure 1, which illustrates a plant for the production of acrylic acid by propane oxidation (according to a preferred embodiment of the invention). In accordance with a preferred embodiment of the invention, the oxygen-containing gas at a predetermined flow rate is directed through the pre-heater to the mixer (1). Part of the stream after the heater is diverted and sent to mix with the stream in reactor R – 1. The scheme also provides for the possibility of supplying an additional amount of oxygen to the line between the reactors R – 2 and R – 3. Propane enters the evaporator, evaporates and is heated to a temperature of 50 to 90 ° C. The resulting stream is sent to a heated mixer (1), where it is mixed with an oxygen-containing gas, recycle gases and water vapor. The gas-vapor stream from mixer (1) is sent to the R – 1 reactor, in which the catalyst for selective oxidation of propylene to acrolein is located at a temperature of 360–400 ° С. The catalyst is in a tube cooled by boiling Dauterm. The degree of conversion of propylene is 90–95%.

After reactor R – 1, fresh oxygen is mixed into the stream and sent sequentially to reactors R – 2 and R – 3. The reactor R – 2 contains a catalyst for the selective oxidation of propane to acrylic acid at a temperature of 360–400 ° С. The catalyst is in a tube cooled by boiling Dauterm. The propane conversion in the R – 2 reactor is 10–15%. In this case, almost all acrolein is oxidized, mainly to acrylic acid. The reaction mixture leaving the R – 2 reactor enters the R – 3 reactor, which also contains a catalyst for the selective oxidation of propane to acrylic acid at a temperature of 360–400 ° С. The catalyst is located in a tube cooled by boiling Dauterm. The total propane conversion in the R – 2 and R – 3 reactors is 20–25%. In addition to acrylic acid, significant amounts of propylene and carbon oxides are formed, as well as small amounts of acetic acid and acrolein. The reaction mixture exiting the R – 3 reactor is fed to an acrylic acid absorber (2) between the packed and plate parts. The absorber (2) consists of two nozzle parts with a disk part between them. The upper nozzle is irrigated using a pump (3) with an aqueous solution of hydroquinone that inhibits the polymerization of acrylic acid. Heated water is supplied to the reflux condenser for cooling, which ensures a residual water vapor content of 30–40% vol. at a temperature of 65–75 ° С. The dish-shaped portion of the absorber is used to condense the bulk of the acrylic acid in the liquid phase with the guaranteed presence of hydroquinone. The lower nozzle of the absorber serves to distill off the propane, which dissolves in the condensate. The temperature of the absorber cube (2) is 103–105 ° С. The absorber cube (2), containing mainly a solution of acrylic acid and acetic acid in water, is removed from the bottom of the absorber (“product”). The separation of acrylic acid from a product containing acrylic, acetic acid and acrolein impurities in water is carried out in an acrylic acid separation unit (not shown in the diagram). This unit can be implemented in any known manner, including may be a system of column apparatus for the isolation and concentration of commercial acrylic acid.

The gas mixture leaving the absorber (2) is fed into the R – 4 reactor, in which there is a catalyst for the selective oxidation of CO in CO ₂ (the catalyst according to Example 1) at a temperature of 60–100 ° С. The catalyst is located in a tube cooled by boiling coolant. The degree of conversion of CO is 50–90%. If necessary, an absorber (2) is also provided with a tap for reburning part of the specified gas mixture in order to avoid its uncontrolled accumulation in the system. The gas mixture leaving the R – 4 reactor, separated from the condensate, is supplied to the compressor (4). After the compressor, part of the reaction mixture is purged. The recirculated gas mixture is fed through a gas flow meter to an alkali absorber (5) for CO ₂ removal. The absorber (5) has the same design as the absorber (2). The upper nozzle is irrigated with an alkali solution supplied by the pump (6), the lower nozzle serves to distill off the propane. The gas mixture leaving the reflux condenser is recycled to the mixer inlet (1).

This method of producing acrylic acid, including the stage of selective oxidation of CO in CO ₂ , allows you to get acrylic acid without the accumulation of carbon oxides in the recycle gases, without loss of hydrocarbons (propane and / or propylene) due to their oxidation on the CO oxidation catalyst (see table .nine).

EXAMPLES

The crystalline phases of the catalyst were identified by X-ray phase analysis (XRD) using the sliding beam method on a Shimadzu XRD – 7000C diffractometer using CuK α radiation (λ = 1.5418 Å) and a Ni filter. Shooting conditions: range 10–80 2Θ, scanning speed 2.0 deg / min, tube voltage 25 kV, current 20 mA.

The specific surface area and porous structure of the catalyst samples were calculated using the single- and multipoint Brunauer, Emmett and Taylor (BET) methods, the STSA (Statistical Thickness Surface Area (STSA) method, ASTM D6556).

Example 1. Preparation of a carbon monoxide oxidation catalyst

2 g of γ – Al ₂ O _{3 were} placed in distilled water with a volume of 100 ml. Sodium carbonate weighing 0.192 g dissolved in 2 ml of distilled water was added to the aqueous suspension of γ – Al ₂ O ₃ . An aqueous solution containing 0.11 g of H ₂ PdCl _4, 5 ml in volume _{, was} added dropwise. Adding a solution of H ₂ PdCl _{4 was} carried out with constant stirring and heating to 90 ° C for 20 minutes. The resulting suspension was kept at a temperature of 90 ° C for 40 minutes. Then added a 30% aqueous solution of sodium formate in an amount of 0.216 g. The resulting suspension was cooled to 25 ° C and the catalyst was separated by filtration. The catalyst was loaded into a tube furnace and calcined in a stream of hydrogen at a temperature of 150 ° C for 30 minutes. Then the catalyst was cooled in a stream of helium and discharged from the tube furnace.

As a result, a catalyst with a palladium content of 2.2% by weight was obtained, which is characterized by texture characteristics (specific surface and porous structure) shown in Table 1.

Table 1 - Textural characteristics of the catalyst obtained in example 1.

Specific surface, m ² / g 267.6 The proportion of micropores,% 1.8% Pore volume, cm ³ / g 0.76 Pore Diameter, nm 5-14

The X-ray phase spectrum (XRD spectrum) of the catalyst obtained in Example 1 is shown in FIG. 2.

As can be seen from FIG. 2, in the XRD spectrum of the catalyst obtained in Example 1, basically all diffraction peaks belong to the γ – Al ₂ O phase _3–46 º, 67 º. In addition, the diffraction peak at 2Θ = 14 °, which belongs to the boehmite phase, is present in the XRD spectrum. Based on quantitative calculations based on an assessment of the peak intensities in the XRD spectrum, the boehmite concentration in the catalyst structure is 1.5–5%.

Example 2. (comparative). Preparation of a carbon monoxide oxidation catalyst with a boehmite phase content of more than 10%.

As a comparison catalyst, a catalyst with a palladium content of 2.2% was used, which is characterized by texture characteristics (specific surface and porous structure) shown in Table 2.

To obtain a catalyst, 2 g of γ – Al ₂ O _{3 were} placed in distilled water with a volume of 100 ml. To the aqueous suspension of γ – Al ₂ O _{3 was} added basic sodium carbonate weighing 0.192 g dissolved in 2 ml of distilled water, as a result of which the pH of the suspension was 11–12. A 5 ml aqueous solution was added portionwise in which 0.11 g of H ₂ PdCl ₄ was dissolved. Adding a solution of H ₂ PdCl ₄ occurred with stirring and heating to 90 ° C for 20 minutes. The resulting suspension was kept at a temperature of 90 ° C for 110 minutes. Then was added a 30% aqueous solution of sodium formate in an amount of 0.216 g. The resulting suspension was cooled to 25 ° C and the catalyst was separated by filtration. The catalyst was loaded into a tubular furnace and calcined in a stream of hydrogen at a temperature of 150 ° C for 30 minutes. Then the catalyst was cooled in a stream of helium and discharged from the tube furnace.

Table 2 - Textural characteristics of the catalyst obtained in example 2.

Specific surface, m ² / g 247.4 The proportion of micropores,% 2.6 Pore volume, cm ³ / g 0.72 Pore Diameter, nm 4,5–16

The XRD spectrum of the catalyst is shown in FIG. 3.

As can be seen from FIG. 3, in the XRD spectrum of the catalyst obtained according to example 2, diffraction peaks at 2Θ equal to 14 °, 18 °, 42 ° and 49 ° belong to the boehmite phase. Based on quantitative calculations, the concentration of boehmite phase in the structure of the catalyst is more than 10% of the mass.

Example 3. (comparative) Preparation of a carbon monoxide oxidation catalyst not containing boehmite phase.

As a comparison catalyst, a catalyst with a palladium content of 2.2% was used, which is characterized by the textural characteristics (specific surface and porous structure) shown in Table 3.

To obtain a catalyst, 2 g of γ – Al ₂ O _{3 was} placed in distilled water with a volume of 100 ml. Basic sodium carbonate weighing 0.192 g, dissolved in 2 ml of distilled water, was added to an aqueous suspension of γ – Al ₂ O ₃ , resulting in a pH of 11– 12. A 5 ml aqueous solution was added portionwise in which 0.11 g of H ₂ PdCl ₄ was dissolved. Adding a solution of H ₂ PdCl ₄ occurred with stirring and heating to 90 ° C for 20 minutes. The resulting suspension was kept at a temperature of 90 ° C for 5 minutes. Then was added a 30% aqueous solution of sodium formate in an amount of 0.216 g. The resulting suspension was cooled to 25 ° C and the catalyst was separated by filtration. The catalyst was loaded into a tubular furnace and calcined in a stream of hydrogen at a temperature of 150 ° C for 30 minutes. Then the catalyst was cooled in a stream of helium and discharged from the tube furnace.

Table 3 - Textural characteristics of the catalyst obtained in example 3.

Specific surface, m ² / g 255.5 The proportion of micropores,% 0.2 Pore volume, cm ³ / g 0.69 Pore Diameter, nm 5–16

The XRD spectrum of the catalyst is shown in FIG. 4.

As can be seen from FIG. 4, in the XRD spectrum of the catalyst obtained according to example 3, all diffraction peaks belong to γ – Al ₂ O ₃ . The boehmite phase was not detected.

Example 4. The method of oxidation of carbon monoxide (CO)

The composition of the reaction mixture (volume%): СО - 3%, О _2–8% , C ₃ H _6–2% , H ₂ O - 30%, dilution gas (N ₂ ) - 57%. As a catalyst, the sample obtained in Example 1 was used. For the process, a tubular reactor with an internal diameter of 26 mm was used. A layer of inert material 10 mm high was loaded at the bottom of the reactor. The catalyst layers (M _layer = 1.2 cm ³ , V _layer = 2.02 g) were alternated with equal volumes of inert material. The diameter of the catalyst granules was 2.5–3.0 mm. The total weight of the loaded catalyst was 11.9 g. The temperature in the catalyst bed was controlled by a thermocouple. Contact time 2 s. The composition of the reaction products was controlled by gas chromatographic analysis.

The experimental results are presented in table 4, from which it follows that at a temperature in the catalyst layer of 102 ° C, the conversion of CO is 61%, and the conversion of propylene does not exceed 4%. Thus, the highest conversion of CO to the presence of propylene, propane and water is achieved at a temperature of 100 ° C or more.

Table 4 - the results of the experiments in example 4.

The temperature in the catalyst layer, ° C Concentration, vol. % Conversion% With C ₃ H ₆ With C ₃ H ₆ 25 3.0 2.0 - - 65 2.61 1.94 13 3 76 2,31 1.93 23 3.2 80 2,30 1.93 23.5 3.3 86 1.88 1.93 37.3 3,5 96 1,56 1.92 48 3,7 102 1.14 1.92 62 4

Example 5. The method of oxidation of carbon monoxide (CO)

The method according to claim 4, in which a reactor with a diameter of 4 mm is used, the weight of the loaded catalyst is 0.88 g. The contact time is 1.1 s. The reaction is carried out at temperatures of 80–140 ° С.

The composition of the initial reaction mass and the composition of the reaction products are at temperatures of 80–140 ° C are presented in table 5. From the experimental results it is seen that the conversion of CO exceeds 50% when carrying out the reaction at temperatures above 100 ° C. This experiment shows the possibility of carrying out the process on the catalyst obtained in example 1, with a contact time of 1.1 s

Table 5 - the results of the experiments in example 5.

The temperature in the catalyst layer, ° C Concentration, vol. % Conversion% With C ₃ H ₆ With C ₃ H ₆ 25 3.0 2.0 - - 80 1.86 1.99 37.87 0.5 one hundred 1.23 1.99 58.92 0.5 120 0.74 1.98 75.25 1 140 0.44 1.99 85.46 0.5

From example 5 it is seen that the conversion of CO on the catalyst obtained according to example 1, when using a reactor with an inner diameter of 4 mm, is 58% at a temperature of 100 ° C and increases to 85% with increasing temperature to 140 ° C. The oxidation of propylene occurs slightly.

Example 6 (comparative). The method of oxidation of carbon monoxide (CO)

The method according to claim 4, in which the catalyst obtained in example 2 is used, the weight of the loaded catalyst is 11.47 g. The contact time is 2.0 s. The reaction is carried out at temperatures of 80–280 ° С.

The composition of the initial reaction mass and the composition of the reaction products at temperatures of 80–280 ° C are presented in Table 6. From the experimental results it is seen that the conversion of CO exceeds 50% when carrying out the reaction at temperatures above 100 ° C.

Table 6 - the results of the experiments in example 6.

Temperature ° C Concentration, vol. % Conversion% With C ₃ H ₆ With C ₃ H ₆ 25 3.0 2.0 - - 80 2.96 1.84 1.15 8.11 one hundred 2.95 1.84 1,56 8.24 120 2.94 1.84 2.14 8.04 150 2.70 1.84 9.87 7.99 160 2.70 1.78 9.98 10.86 180 2.66 1.78 11.45 11.04 200 2.64 1.77 12.01 11.14 220 2.03 1.75 32.32 12.33 240 2.03 1.74 32,42 12.54 260 0.25 1.74 91.54 12.61 280 0 1.17 one hundred 41.5

The results of the experiments in example 6 show that the catalyst obtained in example 2 is characterized by low activity and low selectivity in the oxidation of CO in the presence of propylene, propane and water.

Example 7 (comparative). The method of oxidation of carbon monoxide (CO)

The method of example 4, in which the catalyst obtained in example 3 is used, the weight of the loaded catalyst is 0.87 g. The contact time is 1.1 s. The reaction is carried out in the temperature range 100-140 ° C.

The composition of the initial reaction mass and the composition of the reaction products at temperatures of 100-140 ° C are presented in table 7.

Table 7 - the results of the experiments in example 7.

The temperature of the catalyst layer, ° C Concentration, vol. % Conversion% With C ₃ H ₆ With C ₃ H ₆ 25 3.0 2.0 - - one hundred 1.36 1.98 54.56 0.877 120 1,11 1.97 62.78 1.12 140 0.89 1.97 70.3 1.21

The experimental results show that for carrying out the process of CO oxidation in the presence of propylene, propane and water, it is inappropriate to use the catalyst obtained in example 3.

Example 8 The method of oxidation of carbon monoxide (CO) (life tests)

The method according to claim 5, in which a reactor with a diameter of 4 mm is used, the weight of the loaded catalyst is 0.88 g. The contact time is 1.1 s. The reaction is carried out at a temperature of 100 ° C for 50 hours. The experimental results are shown in table 8, which shows that during the experiment, the conversion of CO on the catalyst obtained in example 1 is at least 50%, and the conversion of propylene does not exceed 1%. This experiment shows the possibility of carrying out the process when achieving the stated result for a long time.

Table 8 - the results of the experiments in example 8.

Time h Concentration, vol. % Conversion% With C ₃ H ₆ With C ₃ H ₆ 0 3.0 2.0 - - 3 0.88 1.99 70.61 0.5 6 0.93 1.99 68.95 0.5 nine 0.87 1.98 70.69 1 12 0.93 1.99 68.81 0.5 15 1.13 1.98 62.01 1 18 1,08 1.99 63.79 0.5 21 0.99 1.98 66.85 1 24 1,52 1.98 50.18 1 27 1.49 1.99 50.08 0.5 thirty 1,50 1.99 50.68 0.5 33 1,52 1.98 50.00 1 36 1,50 1.99 50.87 0.5 38 1.47 1.98 50.84 1 41 1.44 1.98 51.7 0.7 44 1.46 1.98 51,2 0.8 47 1.49 1.99 50,2 0.3 50 1.44 1.99 51.7 0.1

From the results of the experiment of example 8 shows that the use of the catalyst obtained in example 1, in the oxidation of CO, ensures the stability of the catalyst for more than 50 hours.

Example 9. Comparative. The method of oxidation of carbon monoxide (CO) (life tests)

The method according to example 5, in which a reactor with a diameter of 4 mm is used, the mass of the loaded catalyst is 0.92 g. The contact time is 1.1 s. The reaction is carried out at a temperature of 140 ° C for 0 hours. The experimental results are shown in table 9, which shows that after 29 hours of the experiment, the conversion of CO on the catalyst obtained in example 3 is less than 50%, and the conversion of propylene exceeds 1%. This experiment shows the inappropriateness of the process on the catalyst obtained in example 3 for a long time.

Table 9 - the results of the experiments in example 9

Time hour Concentration% Conversion% With C ₃ H ₆ With C ₃ H ₆ 0 3.0 2.0 - - 1 2.97 1.97 71.89 1.19 3 2.91 1.97 62.05 1.19 ten 2.7 1.97 57.44 1.21 15 2,55 1.97 56.71 1.20 20 2,4 1.97 54.97 1.24 21 2,37 1.97 53.61 1.25 23 2,31 1.97 51.27 1.21 25 2.25 1.97 52.26 1.26 29th 2.13 1.97 47,99 1.27 32 2.04 1.97 45.57 1.27 35 1.95 1.97 43,46 1.28 38 1.86 1.97 44.18 1.29 41 1.77 1.97 42.16 1.31 43 1.71 1.97 41.34 1.34 45 1.65 1.97 40.01 1.34 47 1,59 1.97 40.05 1.35 51 1.47 1.97 38.38 1.35 54 1.38 1.97 37.01 1.37 57 1.29 1.96 36.46 1.75 60 1,2 1.97 35.07 1.41

Thus, it can be seen from the experimental results that for the effective implementation of the process of CO oxidation in CO ₂ in the presence of propylene, propane and water, it is necessary to use a catalyst that is a metal of the platinum group, preferably palladium, deposited on a surface of the porous support and which is particularly preferably characterized a combination of the following features:

a catalyst support consisting of γ – Al ₂ O ₃ and an additional phase — boehmite in an amount not exceeding 10 wt. %, preferably from 0.5 to 7% of the mass., more preferably from 1.5 to 5% of the mass.

developed specific surface area of the catalyst is approximately 240-270 m ² / g

the pore volume of the catalyst is from 0.7 to 0.8 cm ³ / g;

average pore size of the catalyst from 7 to 14 nm;

the micropore content of the catalyst is approximately 1.5–2%.

In this case, the oxidation of CO is preferably carried out at a contact time of 1–3 s and a temperature of 100–140 ° С.

Example 9. A method of producing acrylic acid by oxidation of propane

Table 10. The composition of the material flows in the process of obtaining acrylic acid

propane oxygen recycling g / hour mass % nl / hour about. % g / hour mass % nl / hour about. % g / hour mass % nl / hour about. % Propane C ₃ H ₈ 279.49 100.00 142.02 100.00 0.00 0.00 0.00 0.00 1005.62 76.81 5.11 68.04 Propylene C ₃ H ₆ 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 41.55 3.17 0.22 2.95 Acrylic acid 0.00 0.000 0.00 0.00 0.00 0.00 0.00 0.00 0.21 0.02 0.00 0.01 Acrolein 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3.18 0.24 0.01 0.17 Acetic acid 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.20 0.02 0.00 0.01 CO ₂ 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 CO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5.76 0.44 0.05 0.61 H ₂ O 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 56.75 4.34 0.71 9.40 O ₂ 0.00 0.00 0.00 0.00 469.61 99.91 328.73 99.90 154.24 11.78 1.08 14.38 Nitrogen 0.00 0.00 0.00 0.00 0.41 0.09 0.33 0.10 41.71 3.19 0.33 4.44 Total: 279.49 100.00 142.02 100.00 470.02 100.00 329.06 100.00 1309.22 100.00 7.51 100.00 Temperature ° C 30.00 20.00 65.67 Pressure bar 2.53 2.53 2.53 Share of steam 1.00 1.00 1.00

Continuation of table 10

reactor inlet R – 1 reactor inlet R – 2 reactor inlet R – 3 g / hour mass % nl / hour about. % g / hour mass % nl / hour about. % g / hour mass % nl / hour about. % Propane C ₃ H ₈ 1340.81 52.35 681.06 37.81 1340.82 52.35 681.06 37.77 1153.10 45.02 585.76 07/32 Propylene C ₃ H ₆ 43.47 1.70 23.14 1.29 6.02 0.24 3.20 0.18 32.53 1.27 17.32 0.95 Acrylic acid 2.25 0.09 0.70 0.04 2.25 0.09 0.70 0.04 265.29 10.36 82.46 4.52 Acrolein 3.38 0.13 1.35 0.08 50.67 1.98 20.25 1.12 2.39 0.09 0.95 0.05 Acetic acid 1.29 0.05 0.48 0.03 1.29 0.05 0.48 0.03 23.53 0.92 8.78 0.48 CO ₂ 0.05 0.00 0.03 0.00 1.28 0.05 0.65 0.04 19.26 0.75 9.81 0.54 CO 5.76 0.23 4.60 0.26 8.88 0.35 7.10 0.39 47.11 1.84 37.67 2.06 H ₂ O 498.42 19.46 619.70 34.40 516.13 20.15 641.72 35.59 675.00 26.35 839.32 45.95 O ₂ 623.85 24.36 436.67 24.24 591.95 11/23 414.35 22.98 301.06 11.75 210.75 11.54 Nitrogen 42.13 1.65 33.68 1.87 42.13 1.65 33.68 1.87 42.13 1.65 33.69 1.84 Total: 2561.41 100.00 1801.41 100.00 2561.41 100.00 1803.20 100.00 2561.40 100.00 1826.50 100.00 Temperature ° C 120.00 360.00 375.00 Pressure bar 2.53 2.53 2.03 Share of steam 1.00 1.00 1.00

Continuation of table 10

reactor exit R – 3 water (with hydroquinone) for absorber irrigation (2) product (mixture of products. coming to the block selection AK) g / hour mass % nl / hour about. % g / hour mass % nl / hour about. % g / hour mass % nl / hour about. % Propane C ₃ H ₈ 1072.64 41.88 544.89 29.66 0.00 0.00 0.00 0.00 1.39 0.09 0.71 0.04 Propylene C ₃ H ₆ 43.93 1.72 23.39 1.27 0.00 0.00 0.00 0.00 0.05 0.00 0.03 0.00 Acrylic acid 354.59 13.84 110.23 6.00 0.00 0.00 0.00 0.00 352.34 22.33 109.51 6.82 Acrolein 3.41 0.13 1.36 0.07 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Acetic acid 33.10 1.29 12.35 0.67 0.00 0.00 0.00 0.00 31.80 2.02 11.86 0.74 CO ₂ 27.00 1.05 13.74 0.75 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 CO 58.15 2.27 46.50 2.53 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 H ₂ O 740.79 28.92 921.14 50.14 950.66 100.00 1182.05 100.00 1192.47 75.57 1482.63 92.39 O ₂ 185.66 7.25 129.97 7.07 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Nitrogen 42.13 1.65 33.69 1.83 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Total: 2561.39 100.00 1837.25 100.00 950.66 100.00 1182.05 100.00 1578.06 100.00 1604.74 100.00 Temperature ° C 360.00 20.00 113.27 Pressure bar 1.88 1.15 1.60 Share of steam 1.00 0.00 0.00

Continuation of table 10

reactor inlet R – 4 reactor exit R – 4 entrance to the absorber (5) WITH ₂ g / hour mass % nl / hour about. % g / hour mass % nl / hour about. % g / hour mass % l / hour about. % Propane C ₃ H ₈ 1071.25 55.39 544.15 38.47 1071.25 55.39 544.18 39.05 1005.62 70.95 510.88 63.39 Propylene C ₃ H ₆ 43.88 2.27 23.36 1.65 43.88 2.27 23.36 1.68 41.55 2.93 12/22 2.74 Acrylic acid 2.25 0.12 0.70 0.05 2.25 0.12 0.70 0.05 0.21 0.02 0.07 0.01 Acrolein 3.41 0.18 1.36 0.10 3.41 0.18 1.36 0.10 3.18 0.22 1.27 0.16 Acetic acid 1.29 0.07 0.48 0.03 1.29 0.07 0.48 0.04 0.20 0.01 0.08 0.01 CO ₂ 27.00 1.40 13.74 0.97 109.22 5.65 55.59 3.99 108.10 7.63 55.03 6.83 CO 58.15 3.01 46.50 3.29 5.82 0.30 4.65 0.33 5.76 0.41 4.60 0.57 H ₂ O 498.98 25.80 620.41 43.87 498.98 25.80 620.45 44.53 56.75 4.00 70.57 8.76 O ₂ 185.66 9.60 129.96 9.19 155.77 8.05 109.04 7.83 154.24 10.88 107.98 13.40 Nitrogen 42.13 2.18 33.68 2.38 42.13 2.18 33.69 2.42 41.71 2.94 33.36 4.14 Total: 1933.99 100.00 1414.34 100.00 1933.99 100.00 1393.50 100.00 1417.32 100.00 805.95 100.00 Temperature ° C 90.52 100.00 91.75 Pressure bar 1.60 1.40 2.73 Share of steam 1.00 1.00 1.00

Thus, it can be seen from the experimental results (Table 10) that this method of producing acrylic acid, including the stage of selective oxidation of CO in CO2, allows you to get acrylic acid without the accumulation of carbon oxides in the recycle gases, without loss of hydrocarbons (propane and / or propylene ) due to their oxidation on a CO oxidation catalyst.

Claims (69)

1. The catalyst for the selective oxidation of carbon monoxide in the presence of a gas mixture comprising propylene, steam and propane containing particles of a platinum group metal deposited on the surface of a porous carrier containing a γ-Al ₂ O ₃ phase and a boehmite phase in an amount of less than 10 wt. % 2. The catalyst according to claim 1, characterized by a specific surface area of the support of 220 to 280 m ² / g, an average pore size of 7 to 14 nm and a pore volume of 0.6 to 0.9 cm ³ / g. 3. The catalyst according to claim 1, where the gas mixture contains propylene in an amount of from 1 to 3 vol. %, and water vapor in an amount of from 20 to 45 vol. % 4. The catalyst according to claim 1, where the platinum group metal is selected from: rhodium, ruthenium, platinum, palladium, and combinations thereof. 5. The catalyst according to claim 1, where the platinum group metal is palladium, while the palladium content is from 0.5 to 3.0 wt. %, preferably from 1.5 to 2.8 wt. %, even more preferably from 2.0 to 2.4 wt. % 6. The catalyst according to claim 5, where the thickness of the palladium layer deposited on the surface of the porous carrier is from 10 to 250 microns, preferably from 50 to 150 microns. 7. The catalyst according to claim 1, where the porous carrier is a granule with a shape selected from spherical, cylindrical, rings, and combinations thereof. 8. The catalyst according to claim 1, where the content of the boehmite phase is preferably from 0.5 to 7.0 wt. %, preferably from 1.5 to 5.0 wt. % 9. The catalyst according to claim 1, wherein the specific surface area of the catalyst is from 240 to 270 m ² / g. 10. The catalyst according to claim 1, wherein the pore volume of the catalyst is from 0.7 to 0.8 cm ³ / g. 11. The catalyst according to claim 1, where the content of micropores of the catalyst, namely pores with a size of less than 2 nm, is from 1 to 5%, preferably 1.5%. 12. The catalyst according to claim 1, where the platinum group metal particles are deposited on the outer surface of the porous carrier. 13. A catalyst for the selective oxidation of carbon monoxide in the presence of a gas mixture comprising propylene, water vapor and propane containing platinum group metal particles deposited on the surface of a porous carrier containing a γ-Al ₂ O ₃ phase and a boehmite phase in an amount of less than 10 wt. %, characterized by at least the following main diffraction peaks in the x-ray phase diagram: 14 °, 46 °, 67 °. 14. A method for the selective oxidation of carbon monoxide by reacting a gaseous mixture comprising carbon monoxide, propylene, water vapor, propane, in the presence of a catalyst according to any one of claims. 1-13. 15. The method according to p. 14, in which the interaction of the gaseous mixture is carried out in a tubular reactor. 16. The method according to p. 14, carried out at a temperature of from 60 to 160 ° C, preferably at a temperature of from 80 to 140 ° C, more preferably from 80 to 120 ° C. 17. The method according to p. 14, where the gaseous mixture contains carbon monoxide in an amount of from 2 to 4 vol. %, propylene in an amount of from 1 to 3 vol. %, water vapor in an amount of from 20 to 45 vol. % 18. The method according to p. 14, where the interaction of the gaseous mixture is carried out in a tubular reactor with a tube diameter in the range from 10 to 60 mm, preferably from 20 to 50 mm 19. The method according to p. 15, where the catalyst is loaded into the reactor in layers alternating with layers of inert material, so that the inert material layer is 1.1-2 times larger in volume than the catalyst layer. 20. The method according to p. 15, where the interaction of the gaseous mixture is carried out at an overpressure in the reactor in the range from 0.1 to 0.5 bar, preferably from 0.1 to 0.3 bar. 21. The method according to p. 14, where the contact time of the catalyst with the gaseous mixture is from 0.5 to 10 s, preferably from 1 to 3 s. 22. A method for producing acrylic acid by heterogeneous oxidation of propane, comprising the steps of: a) a feed gas stream containing propane, water vapor and an oxidizing agent is fed to a reactor containing a catalyst for the selective oxidation of propane to acrylic acid, to obtain a gaseous mixture containing acrylic acid, unreacted propane and propylene, as well as carbon oxides, b) the gaseous mixture obtained in step a) is fed to the separation step to separate acrylic acid and produce a gaseous mixture including propane, propylene, steam, and carbon oxides, c) the gaseous mixture obtained in step b) is fed to a carbon monoxide selective oxidation reactor containing a carbon monoxide selective oxidation catalyst according to any one of claims. 1-13, where the oxidation of carbon monoxide is carried out according to the method according to any one of paragraphs. 14-21, d) a gaseous mixture exiting the carbon monoxide selective oxidation reactor is fed to a water separation and carbon dioxide purification step, and e) the gaseous mixture enriched in propane and propylene after step d) is returned to step a). 23. The method according to p. 22, further containing a stage in which prior to supplying a feed gas stream to a reactor containing a catalyst for selective oxidation of propane to acrylic acid, said gas stream is fed to a reactor containing a catalyst for selective oxidation of propylene to acrolein. 24. The method according to p. 23, in which the gaseous mixture obtained in stage a) contains minor amounts of acrolein and acetic acid. 25. The method according to p. 22, in which the oxidizing agent includes molecular oxygen in pure form or in a mixture with inert gaseous diluents. 26. The method according to p. 22, in which the content of water vapor is from 20 to 45 vol. %, preferably from 20 to 35 vol. %, more preferably from 20 to 30 vol. % 27. The method according to p. 22, in which the conversion of propane is from 5 mol. % to 30 mol.%, preferably from 20 to 25 mol. % 28. The method according to p. 22, in which the selective oxidation of propane to acrylic acid is carried out at a temperature of from 320 to 420 ° C. 29. The method according to p. 22, in which the selective oxidation of propane to acrylic acid is carried out at a pressure of from 0.5 to 5 bar, preferably from 1 to 3 bar. 30. The method according to p. 22, in which stage a) is carried out in one reactor. 31. The method according to p. 22, where stage a) is carried out in two or more series-connected reactors. 32. The method according to p. 22, in which stage a) is carried out in two or more parallel reactors. 33. The method according to any one of paragraphs. 20, 30-32, where stage a) is carried out in a tubular reactor. 34. The method according to p. 33, where a coolant is used in a tubular reactor, which is selected from molten salts, low-melting metals or diphenyl mixtures. 35. The method according to p. 22, where stage a) is carried out in the presence of a catalyst, the temperature of which exceeds the temperature of the coolant by 40-60 ° C. 36. The method according to p. 34, where the temperature of the coolant in the tubular reactor is from 260 to 310 ° C. 37. A method of producing a catalyst according to any one of paragraphs. 1-13, containing stages in which: a) provide a catalyst carrier containing gamma alumina and a boehmite phase in an amount of up to 10 wt. % b) reducing the platinum group metal on the surface of the catalyst support by adding a reducing agent; c) cooling the resulting mixture to room temperature, followed by isolation of the catalyst from the mixture; d) drying the catalyst, e) restore the resulting catalyst in a stream of hydrogen; f) passivate the catalyst in an inert gas stream. 38. The method of claim 37, wherein the platinum group metal is selected from: rhodium, ruthenium, platinum, palladium. 39. The method of claim 37, wherein the platinum group metal is palladium. 40. The method of claim 37, wherein the step of providing the catalyst carrier comprises the following sub-steps: i) preparing an aqueous suspension of γ-Al ₂ O ₃ , ii) add to the specified suspension of the main precipitant, iii) add a precursor containing a metal of the platinum group, followed by stirring, heating the resulting mixture and keeping it for a predetermined time. 41. The method according to p. 40, in which the main precipitant includes potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, or combinations thereof. 42. The method according to p. 40, in which the pH of the medium is maintained at a constant level of approximately 9-11, preferably 10. 43. The method of claim 39, wherein the precursor containing the platinum group metal is a palladium-containing precursor and includes compounds selected from H ₂ PdCl ₆ , Pd (NO ₃ ) ₂ , [Pd (NH ₃ ) ₂ Cl ₂ ], H ₂ PdCl ₄ . 44. The method according to p. 40 or 43, in which a precursor containing a platinum group metal is added dosed over a period of time from 10 to 30 minutes at a temperature of from 70 to 80 ° C. 45. The method according to p. 40 or 43, in which after dosing a precursor containing a platinum group metal, the catalyst suspension is maintained for a period of time from 20 minutes to 60 minutes, at a temperature of from 70 to 100 ° C. 46. The method of claim 40, wherein the reducing agent includes a solution of a weak organic acid salt and a strong base. 47. The method of claim 40, wherein the reducing agent is selected from the group consisting of sodium formate, ammonium acetate, ammonium formate, and ammonium oxalate. 48. The method according to p. 40, in which after the stage of separation of the catalyst is purified from chloride ions. 49. The method according to p. 37, in which the obtained catalyst is subjected to drying at temperatures from 40 to 150 ° C. At atmospheric pressure and / or pressure much lower than atmospheric. 50. The method according to p. 40 or 43 in which the recovery of the precursor to a metallic state on the surface of the catalyst is carried out in a stream of hydrogen in a tube furnace for a period of time from 30 to 60 minutes at temperatures from 100 to 200 ° C, preferably from 120 to 180 ° C, more preferably 140 to 160 ° C. 51. The method of claim 37, wherein the reduced catalyst is cooled in a stream of an inert gas selected from argon, nitrogen, or helium. 52. The method according to p. 43, in which the molar ratio of reactants Pd: basic precipitant: reagent reductant is maintained in the range of 1: (10-2) :( 4-1), most preferably 1: 4: 1.5. 53. The method according to p. 40, in which the conversion of γ-Al ₂ O ₃ into boehmite is carried out by selecting the conditions for carrying out stages i-iii to shift the thermodynamic equilibrium towards the formation of the boehmite phase. 54. The method according to p. 40, in which to shift the thermodynamic equilibrium towards the formation of the boehmite phase from the γ-Al ₂ O ₃ phase, γ-AL ₂ O ₃ is maintained in the presence of water at a temperature of from 80 to 100 ° C for a period of time from 20 minutes to 60 minutes 55. The method according to p. 37, in which the content of the boehmite phase is from 0.5 to 7.0 wt. %, preferably from 1.5 to 5.0 wt. %

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