Catalyst for selective oxidation of hydrogen sulfide, method of preparation thereof, and a process of selectively oxidizing hydrogen sulfide to elemental sulfur

FIELD: gas treatment processes and catalysts.

SUBSTANCE: invention relates to catalyst for selectively oxidizing hydrogen sulfide to sulfur in industrial gases containing 0.5-3.0 vol % hydrogen sulfide and can be used at enterprises of gas-processing, petrochemical, and other industrial fields, in particular to treat Claus process emission gases, low sulfur natural and associated gases, chemical and associated petroleum gases, and chemical plant outbursts. Catalyst for selective oxidation of hydrogen sulfide into elementary sulfur comprises iron oxide and modifying agent, said modifying agent containing oxygen-containing phosphorus compounds. Catalyst is formed in heat treatment of α-iron oxide and orthophosphoric acid and is composed of F2O3, 83-89%, and P2O5, 11-17%. Catalyst preparation method comprises mixing oxygen-containing iron compounds with modifying agent compounds, extrusion, drying, and heat treatment. α-Iron oxide used as oxygen-containing iron compound is characterized by specific surface below 10 m2/g, while 95% of α-iron oxide have particle size less than 40 μm. Orthophosphoric acid is added to α-iron oxide, resulting mixture is stirred, dried, and subjected to treatment at 300-700°C. Hydrogen sulfide is selectively oxidized to elemental sulfur via passage of gas mixture over above-defined catalyst at 200-300°C followed by separation of resultant sulfur, O2/H2S ratio in oxidation process ranging from 0.6 to 1.0 and volume flow rate of gas mixture varying between 900 and 6000 h-1.

EFFECT: increased yield of elemental sulfur.

9 cl, 5 tbl, 9 ex

 

The invention relates to a catalyst for selective oxidation of hydrogen sulfide, the method thereof and method of selective oxidation of hydrogen sulfide to sulfur in the industrial gases containing 0.5 to 3.0% vol. of hydrogen sulfide, and can be used on gas processing plants, petrochemical and other industries, in particular for purification of exhaust gas of the Claus process, low-sulfur natural gas and associated petroleum gas, emissions, chemical production.

Now for the extraction of sulfur from gases of different origin, containing low concentrations of hydrogen sulfide, apply methods based on the oxidation of hydrogen sulfide to sulfur by the reaction:

in the gas phase in the presence of the solid catalyst ("Improved Claus sulphur recovery: Keeping abreast of the regulations, Sulphur, 1994, No. 231, p.35-59). The practical realization of this reaction with high yield of sulfur is difficult for a number of reasons. The oxidation reaction of hydrogen sulphide into sulphur can effectively take place in a limited temperature interval (180-300° (C): the upper temperature limit due to the possibility of a homogeneous reaction of the oxidation of sulfur in the SO2at a higher temperature, the lower the deactivation of the catalyst due to the condensation of sulfur on the catalyst surface.

In addition, the selective behaviour is ity oxidation of hydrogen sulfide to sulfur may be reduced due to the occurrence of several side reactions. In particular, the selectivity may be reduced due to oxidation of sulfur is condensed on the surface of the catalyst:

or due to the oxidation of hydrogen sulfide to sulfur dioxide:

In the presence of gases, water vapor using catalysts active in the Claus reaction, such as aluminum oxide and titanium dioxide, can lead to reduction of yield of sulfur due to the reversible flow the Claus reaction towards formation of sulphur dioxide:

The problem of deep purification of exhaust gases by selective oxidation of hydrogen sulfide to sulfur is to create a catalyst capable of selectively oxidizing hydrogen sulfide to elemental sulfur according to reaction (1) and does not contribute to the occurrence of adverse reactions(2)-(4).

Known catalyst used for oxidation of hydrogen sulfide with oxygen in sulfur containing as active components, oxides of iron and vanadium deposited on the aluminum oxide with SID>30 m2/g and Vthen0.4-0.8 cm3/g (U.S. Patent No. 4197277, CL. 01 In 17/04, 1980). However, the aluminum oxide with such a value of specific surface area still contains some amount of phase γ-Al2About3that is active in the Claus reaction, and thus contribute to the t reduction of yield of sulfur due to the occurrence of the reverse Claus reaction (4).

Known iron oxide catalyst for oxidation of hydrogen sulfide to sulfur in natural gas (A.S. USSR №871813, CL. 01 In 17/04, 1981), characterized by low specific surface (2 cm2/g), developed porous structure and an average pore - 2500 Å. Oxidation of hydrogen sulfide in the presence of this catalyst is recommended in the presence of excess (2-12 times) compared with the stoichiometric required amount of oxygen, which increases the probability of formation of sulphur dioxide according to reaction (2) and may lead to a decrease in selectivity with increasing temperature. Indeed, the degree of conversion of hydrogen sulphide into sulphur on the catalyst at 275°amounts to 89.5%at 300°Of 62.3% (A.S. No. 967551, CL. B 01 J 23/74, 1982). Moreover, the catalyst has low mechanical strength and is suitable for the purification of gas streams containing water vapor.

A known catalyst (A.S. No. 967551, CL. B 01 J 23/74, 1982) for sulfur by oxidation of sulfide by oxygen containing 11,1 23.5 wt.% iron oxide deposited on a silica-alumina porcelain media composition, wt.%: aluminum oxide 22,4-24,0; magnesium oxide 0,59-0,62; calcium oxide 0,66-0,73, potassium oxide 0.3 to 0.4; sodium oxide 0,23-0,25, silicon oxide - rest. One disadvantage of this catalyst is the complex ways the cooking, including in the first stage, the preparation of a carrier by mixing a mixture of powders of kaolin, clay and quartz sand with water followed by molding of the obtained paste cuttings drying at a temperature of 120°C for 14 h and annealed in air for 30 hours at a temperature of 1200°; and the second stage impregnation of the carrier with a solution of nitrate of iron (III) with subsequent evaporation of the excess solution on a water bath under continuous stirring, drying at 120°and annealing at 650°C for 4 h The described method of preparation of the catalyst is very uneconomical because of the need to prepare powders of fine grinding, ignited the carrier and the catalyst at a high temperature for a long time, and the use of natural raw materials (clay, sand) and the complex procedure of impregnation it difficult to obtain a catalyst with reproducible properties by this method on an industrial scale.

A known catalyst for the oxidation of hydrogen sulfide to sulfur (A.S. No. 856974, CL. 01 In 17/04, 1981); containing oxides of iron and titanium, with the following content of components, wt.%: iron oxide is 0.05 to 3.0, titanium dioxide - the rest. However, the high activity of this catalyst can only be achieved when carrying out the process in two stages, with separate supply of oxygen to each stage and mandatory ulali what W formed sulfur and water at each stage. In addition, the presence of a catalyst of titanium dioxide, which has, as is well known, high catalytic activity in the reaction Claus, will not allow to achieve a high yield of sulfur purification of gas mixtures containing water vapor, due to leakage in the reversible reaction of clause (4).

Known porous solid oxide catalyst (U.S. Patent No. 5603913, CL. 01 In 17/16, 1997) for the selective oxidation of hydrogen sulfide to sulfur, in which the atomic ratio of the metals correspond to the formula FeAMgBZnWithCrDwhere A=0.5 To 10, In=0.1 to 10, C=0-1, D=0-1, b+C=1, the specific surface of the catalyst is 1-5 m2/g, at least 90% of the pores have a diameter greater than 500 Å. Selective oxidation is performed by passing a gas stream containing hydrogen sulfide and oxygen over the catalyst at a volumetric rate 100-6000 h-1and in the temperature range 180-300°C. the Catalyst is prepared by precipitation of metal hydroxides from a solution containing salts of one or more metals, by adding to this solution a solution of ammonia or alkali to a pH of 10-11, followed by filtration ready precipitate, wash, molding, drying, and calcination at a temperature of 600-1000°C. This method of cooking is not possible to obtain granules of the catalyst with sufficient strength. Another disadvantage of this catalysis is ora is the presence of large amounts of filtrate and wash water, contaminated metal cations, nitrate and chloride ions. In addition, one of the components of the catalyst - chrome - is toxic.

In U.S. patent No. 5891415 (CL. 01 In 17/16, 1999) process for selective oxidation of hydrogen sulfide into elemental sulfur is proposed to use a porous oxide catalyst in which the metal content corresponds to the formula FeAZnandwhere A=0.5 To 10, B=1-2, the specific surface area is 2-5 m2/g, more than 90% of the pores have a size greater than 500 Å. The catalyst is prepared by mixing oxides of iron and zinc, crushed in a ball mill by the method of wet grinding so that the atomic ratio of Fe2About3:ZnO=1:1. The resulting paste podvalivaet at room temperature for 24 h, reaching a moisture 32-33%, the paste is formed into the cuttings with a diameter of 4 mm, a length of 4-6 mm, dried at 140°C, then calcined in air for 3.5 hours at a temperature of 600-1000°C. Selective oxidation is performed by passing a gas stream containing hydrogen sulfide and oxygen over the catalyst at a volumetric rate 100-6000 h-1and in the temperature range 180-300°C. the Main disadvantage of this catalyst is the need for strict compliance with the stoichiometric ratio of Fe and Zn and procedures calcination in order to ensure complete binding of individual oxide is in Fe and Zn in the zinc ferrite, as the active component of the catalyst is a zinc ferrite, and the presence of free phase oxides, not related to the spinel leads to rapid deactivation and reduction of selectivity (Saleh Abdulhamid, Salim Ali, Kozarov A.I., mirzaee JI Partial oxidation of hydrogen sulfide on ferrite catalysts. WPI. Colleges of Azerbaijan, 2000, N 5, 25-33).

The most close, essentially, is the catalyst that contains at least one catalytically active component in an amount of 1-10 wt.%, selected from the group of oxides: iron, chromium, manganese, cobalt and/or Nickel, as promoting additives contains phosphorus compounds and/or alkali metals in a quantity of 0.05 to 1.0 wt.%, on the media - silicon oxide, and is characterized by the Sbeats- 20-350 m2/g and an average pore 32-2980 Å (RF Patent No. 2070089, CL. 01 In 17/04, B 01 J 23/86, 1989). The catalyst according to the invention may additionally contain as a promoter from 0.05 to 1 wt.% phosphorus compounds or sodium. The catalyst is suitable for the oxidation of hydrogen sulfide with oxygen in a fixed or fluidized bed at a temperature of 150-330°and a molar ratio of O2/H2S, is equal to 0.5 to 1.5, in a gas mixture containing 1.5 vol.% H2S, 30% vol. steams. The catalyst is prepared by impregnation of the carrier by capacity solutions containing complexes ethylendiamin is of iron leads to compounds, which, ethylenediaminetetraacetic acid, a solution of cellulose and salt solutions promoting compounds. The disadvantages of the method of preparation of the catalyst are the use of complex and expensive iron complexes with organic ligands as a precursor of the active component, a strict regulation of the stage of applying the catalytically active material on the carrier, the stages of drying and calcination of the catalyst is required to obtain a catalyst with a uniform distribution of the active component. The disadvantage of oxidation of hydrogen sulfide in the presence of this catalyst is the need to use excessive compared with the stoichiometric concentration of oxygen to prevent deactivation of the catalyst, as in these conditions increases the likelihood of oxidation of sulfur, especially at temperatures above 250°C.

The main disadvantage of this catalyst is that a high yield of sulfur (above 80%) is achieved in a narrow temperature interval (240-280°). Described in this patent, the catalyst is not a high activity at low temperatures, as a result, when the temperature is 240°With the release of sulfur is not more than 60%. At temperatures above 270°With the selectivity of the conversion of hydrogen sulfide into sulfur and sulfur recovery begin to somatomedins due to the formation of SO 2that leads to a reduction of yield of sulfur, which at 300°is only 62%.

The basis of the offer of the invention is the development of catalyst and method of oxidation of hydrogen sulfide with oxygen to sulfur in the presence of 0-30% vol. water vapor, providing a higher yield of sulfur at the stage of oxidation in the temperature range 200-300°compared to the prototype.

This object is achieved by using a catalyst for the selective oxidation of hydrogen sulfide into elemental sulfur, comprising iron oxide and modifying additive. As a modifying additive catalyst contains oxygen-containing phosphorus compounds, and the catalyst formed during the heat treatment α-iron oxide and phosphoric acid and has the following composition, wt.% in terms of oxides: Fe2About383-89; P2About511-17.

Total pore volume of the catalyst is in the range of 0.08-0.25 cm3/year

The catalyst preferably contains pores with a radius of 40-500 Å less than 20% of the total pore volume, and specific surface area is less than 10 m2/g of catalyst.

The catalyst may further comprise a promoter in the form of at least one metal oxide selected from the group of: chromium, zinc, manganese, cobalt, cerium, zirconium in an amount of from 0.01 to 2 wt.%.

The catalyst may shall be made in the form of cuttings, rings, the unit cell structure.

The task is achieved using the method of preparation of the catalyst for selective oxidation of hydrogen sulfide into elemental sulfur, comprising a mixture of oxygen-containing compounds of iron and compounds modifying additives, extrusion, drying and heat treatment. As oxygen-containing compounds of iron use αoxide of iron, which has a specific surface area of less than 10 m2/g and 95% α-iron oxide has a particle size less than 40 μm, it α-iron oxide type compound modifying additives - phosphoric acid, mixed, dried, and conducting heat treatment at a temperature of 300-700°C.

When the mixture of iron compounds and phosphoric acid is further added if necessary plasticizing agents in an amount up to 5 wt.%.

The objective is also achieved using the method of selective oxidation of hydrogen sulfide into elemental sulfur by passing the gas mixture over the catalyst at a temperature of 200 to 300°followed by the separation of the formed sulfur. The oxidation is carried out in the presence of a catalyst, the ratio O2/N2S varies in the range of 0.6-1.0 and bulk transmission rate of the gas mixture is 900-6000 h-1.

The water vapor concentration in the reaction mixture may be 0-30%vol.

Great for the consistent feature of the proposed method for the oxidation of hydrogen sulfide into elemental sulfur is the use of a catalyst, containing αoxide of iron and oxygen-containing phosphorus compounds, and oxidation of hydrogen sulfide at a ratio of About2/H2S, not exceeding 1.0. Carrying out the oxidation reaction of hydrogen sulfide at conditions where the ratio of O2/H2's close to the stoichiometric required for the selective oxidation of hydrogen sulfide to sulfur, reduces the probability of the reaction of oxidation of the sulfur with oxygen to form sulfur dioxide, especially at temperatures above 250°C.

This set of distinctive features is attached to the object properties that allow it to achieve its goal, the use of the catalyst and method of oxidation of hydrogen sulfide into elemental sulfur provides a higher yield of sulfur in the temperature range 200-300°compared to the prototype.

The catalyst is prepared as follows.

In the mixer load αoxide of iron, 95% of which have a particle size less than 40 microns. Under continuous stirring, phosphoric acid, diluted with water. Optionally, the catalyst is injected modifying additives. The mass is stirred, molded, dried, hold the heat and get the catalyst of a given composition.

Table 1 presents the conditions for preparation of the catalyst. In tables 2-5 presents the catalytic properties.

The essence of the invention is illustrated by the following examples:

Example 1

For the preparation of a catalyst mass in the mixer load 300 g α-iron oxide, 95% of which have a particle size less than 40 microns, and under continuous stirring, 40 ml of orthophosphoric acid, 50 ml of water and 10 ml of glycerol. After stirring for 30-60 min weight molded, dried at a temperature of 100-120°C for 4 h, and calcined at a temperature of 400°C for 5 hours, the Catalyst has the shape of a handle.

The catalytic properties of the sample are determined with the help of pellets of the catalyst in the form of cuttings with a diameter of 5 mm and a length of 5-6 mm in a flow type reactor at flow rate of 4000 h-1concentrations of hydrogen sulfide (volume fraction, %) - 1,2; the water vapor concentration (volume fraction, %) - 30, the value Of2/H2S, is equal to 0.8. The temperature was raised stepwise, with an interval of 20°from 200 to 300°With, then reduced in reverse order. Catalytic properties characterize the degree of conversion of hydrogen sulfide, selectivity and yield of sulfur, the magnitude of which is calculated according to the results of determination of input and output concentrations of the reactants through the chromatograph.

The results of the comparison of the catalytic properties of this catalyst solution (example 10 from the description of the patent of the Russian Federation No. 2070089), not only the us in table 2.

Example 2

Similar to example 1, except for the preparation of the catalyst are added 50 ml of orthophosphoric acid and calcination of the catalyst is carried out at 700°C.

Catalytic properties determined according to the procedure described in example 1.

Example 3

Similar to example 1, except that the calcination of the catalyst is carried out at a temperature of 300°C. the Catalyst is in the form of rings.

Determination of catalytic properties, make use of a fraction of a catalyst with a particle size of 0.4-0.6 mm in a flow type reactor with a volumetric speed 12000 h-1concentrations of hydrogen sulfide (volume fraction, %) - 1,2; the water vapor concentration (volume fraction, %) - 30, the ratio of O2/H2S, is equal to 0.8. The temperature was raised stepwise, with an interval of 20°from 200 to 300°S, then decrease in the same order. Catalytic properties characterize the degree of conversion of hydrogen sulfide, selectivity and yield of sulfur, the magnitude of which is calculated according to the results of determination of input and output concentrations of the reactants through the chromatograph.

The results of the comparison of the catalytic properties of this catalyst solution (example 4 from the description of the patent of the Russian Federation No. 2070089) are presented in table 3.

Example 4

Similar to example 1, only with stirring, add 30 ml of orthophosphoric acid as a plasticizer use the form polyethylene oxide and the catalyst is formed in a unit cell structure.

The catalytic properties were determined according to the method described in example 3, characterized in that the ratio of O2/N2S is 1.

Example 5

Similar to example 1, only in α-iron oxide type promoter - cerium oxide in an amount of 0.01 wt.% and do not use softener.

The catalytic properties were determined according to the method described in example 3, characterized in that the ratio of O2/H2S is equal to 0.6.

Example 6

Similar to example 1, only in α-iron oxide is injected promoters - zirconium oxide in the amount of 1.5 wt.% and the cerium oxide in the amount of 0.5 wt.% and do not use softener.

The catalytic properties were determined according to the method described in example 1. Characterized in that the volume flow rate is 900 h-1. The results are presented in table 4.

Example 7

Similar to example 1, except that the iron oxide as promoters injected zinc oxide in the amount of 0.5 wt.% and manganese oxide in the amount of 1.5 wt.%. The catalytic properties were determined according to the method described in example 1. The difference is that the water vapor content in the reaction mixture is 20 vol.%. The results are presented in table 5.

Example 8

Similar to example 1, except that the iron oxide as promoters enter the chromium oxide and cobalt oxide in an amount of 1.0 wt.% each. Catalytic properties determine elali according to the method described in example 1. The difference is that the water vapor content in the reaction mixture is 10 vol.%. The results are presented in table 5.

Example 9

Similar to example 1, except for preparing the catalyst is not used plasticizer. The catalytic properties were determined according to the method described in example 1. Characterized in that the reaction mixture does not contain water vapor. The results are presented in table 5.

Comparison of the results of the study dependence of the yield of sulfur on temperature is known and the proposed catalysts are presented in table 2 and 3 shows that the proposed catalyst for selective oxidation of hydrogen sulfide to sulfur provides technical result: higher yield of sulfur in the entire investigated temperature interval. The use of the catalyst due to the higher activity per unit volume will allow you to use a smaller load to obtain a high yield of sulfur and to increase the capacity of existing reactors. The data presented in table 4, indicate that the change in the volumetric gas flow rate from 4000 h-1up to 900 h-1almost no influence on the yield of sulfur. This will ensure high efficiency industrial flue gases from hydrogen sulphide in the processing of gases with variable speed ha the new thread for example, exhaust gases Claus process in oil refineries. The data presented in table 5 show that the proposed method for the oxidation of hydrogen sulfide allows to achieve a high yield of sulfur regardless of the concentration of water vapor in the recycled gas and therefore suitable for desulfurization hydrogen sulfide-containing gases of different origin, such as exhaust gases of the Claus process, fuel gas, gas coke ovens, vibronic gases of different chemical plants and other

Table 2.
Catalytic properties
# exampleThe reaction temperature, °The degree of transformation of H2S %The selectivity of the conversion of H2S to sulfur, %The output of sulfur, %
1200559854
220679866
240859782
260919788
2809496300988987
2200749873
220879684
240899585
260989391
2801008888
3001007676
200159614
example 10220349633
description240579554
patent of the Russian Federation260839377
No. 2070089280989088
3001005656

Table 5.
Catalytic properties
# exampleWater vapor concentration, % vol.The reaction temperature, °The degree of transformation of H2S %The selectivity of the conversion of H2S to sulfur, %The output of sulfur, %
7202005510055
220679966
240869884
260959792
280969792
300999291
8102005610056
2206810068
240879885
260939790
280979491
3001009292
902006410064
2207410074
240899685
260979491
2801009292
3001009191

1. Catalyst for selective oxidation of hydrogen sulfide into elemental sulfur, comprising the iron oxide and the modifying additive is a compound of phosphorus, characterized in that as modifying additives it contains oxygen-containing phosphorus compounds, and the catalyst formed during the heat treatment α-iron oxide and phosphoric acid and has the following composition, wt.% in terms of the oxide:

Fe2O383-89

P2O511-17.

2. Kata is isator according to claim 1, wherein the total pore volume is in the range of 0.08-0.25 cm3/year

3. The catalyst according to claim 1, characterized in that it contains pores with a radius of 40-500 Å less than 20% of the total pore volume and specific surface area is less than 10 m2/g of catalyst.

4. The catalyst according to claim 1, characterized in that it further contains a promoter in the form of at least one metal oxide selected from the group of: chromium, zinc, manganese, cobalt, cerium, zirconium in an amount of from 0.01 to 2 wt.%.

5. The catalyst according to claim 1, characterized in that it is made in the form of a shank, ring, block cell structure.

6. A method of producing a catalyst for selective oxidation of hydrogen sulfide into elemental sulfur, comprising a mixture of oxygen-containing compounds of iron and compounds modifying additives, extrusion, drying and heat treatment, characterized in that as the oxygen-containing compounds of iron use αoxide of iron, which has a specific surface area of less than 10 m2/g and 95% α-iron oxide has a particle size less than 40 μm, it α-iron oxide type compound modifying additives - phosphoric acid, mixed, dried, and conducting heat treatment at a temperature of 300-700°C.

7. The method according to claim 6, characterized in that when a mixture of iron compounds and phosphoric acid optionally enter the t plasticizing agents in an amount up to 5 wt.%.

8. The method of selective oxidation of hydrogen sulfide into elemental sulfur by passing the gas mixture over the catalyst at a temperature of 200 to 300°followed by the separation of the formed sulfur, characterized in that the oxidation is carried out in the presence of a catalyst according to any one of claims 1 to 5, the ratio of the O2/H2S varies in the range of 0.6-1.0 and bulk transmission rate of the gas mixture is 900-6000 h-1.

9. The method according to claim 8, characterized in that the water vapor concentration in the reaction mixture is 0-30%vol.



 

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16 cl, 2 dwg, 2 tbl

FIELD: engineering of Fischer-Tropsch catalysts, technology for producing these and method for producing hydrocarbons using said catalyst.

SUBSTANCE: catalyst includes cobalt in amount ranging from 5 to 20 percents of mass of whole catalyst on argil substrate. Aforementioned substrate has specific surface area ranging from 5 to 50 m2/g. Catalyst is produced by thermal processing of argil particles at temperature ranging from 700 to 1300°C during period of time from 1 to 15 hours and by saturating thermally processed particles with cobalt. Method for producing hydrocarbon is realized accordingly to Fischer-Tropsch method in presence of proposed catalyst.

EFFECT: possible achievement of high selectivity relatively to C5+ at low values of diffusion resistance inside particles.

3 cl, 9 ex, 9 dwg

FIELD: structural chemistry and novel catalysts.

SUBSTANCE: invention provides composition including solid phase of aluminum trihydroxide, which has measurable bands in x-ray pattern between 2Θ=18.15° and 2Θ=18.50°, between 2Θ=36.1° and 2Θ=36.85°, between 2Θ=39.45° and 2Θ=40.30°, and between 2Θ=51.48° and 2Θ=52.59°, and has no measurable bands between 2Θ=20.15° and 2Θ=20.65°. Process of preparing catalyst precursor composition comprises moistening starting material containing silicon dioxide-aluminum oxide and amorphous aluminum oxide by bringing it into contact with chelating agent in liquid carrier and a metal compound; ageing moistened starting material; drying aged starting material; and calcining dried material. Catalyst includes carrier prepared from catalyst composition or catalyst precursor and catalytically active amount of one or several metals, metal compounds, or combinations thereof. Catalyst preparation process comprises preparing catalyst carrier from starting material containing silicon dioxide-aluminum oxide and amorphous aluminum oxide by bringing it into contact with chelating agent and catalytically active amount of one or several metals, metal compounds, or combinations thereof in liquid carrier, ageing starting material; drying and calcinations. Method of regenerating used material involves additional stage of removing material deposited on catalyst during preceding use, while other stages are carried out the same way as in catalyst preparation process. Catalyst is suitable for treating hydrocarbon feedstock.

EFFECT: improved activity and regeneration of catalyst.

41 cl, 3 dwg, 8 tbl, 10 ex

FIELD: oxidation catalysts.

SUBSTANCE: invention relates to sorption engineering and can be used for regeneration of different kinds of hopcalite lost catalytic activity during long-time storage. Regenerated sorbents can be used un respiratory masks and in processes or removing carbon monoxide from industrial emissions. Invention provides a method for activating carbon monoxide oxidation catalyst involving heat treatment thereof and characterized by that activation is conducted by heating catalyst bed 2-3 cm thick to 180-380°C at temperature rise velocity 10-20°C/min while constantly carrying away reactivation products.

EFFECT: enabled restoration of catalytic activity.

3 ex

FIELD: catalyst preparation.

SUBSTANCE: invention relates to supported catalysts and provides a method for preparing catalyst-containing solid product comprising step, wherein ceramic carrier is applied onto metallic surface, and depositing catalytically active material onto ceramic carrier, which was preliminarily coated with supporting porous metallic material, ceramic carrier being applied onto and/or into supporting porous metallic material. Invention also describes device used in preparation of catalyst-containing solid product for applying supporting porous material onto inside or outside metallic surfaces of the hollow body.

EFFECT: increased stability of catalyst.

7 cl, 2 dwg

FIELD: production of carbon carrier for catalysts.

SUBSTANCE: proposed method includes heating of moving layer of granulated furnace black used as backing, delivery of gaseous or vaporous hydrocarbons into soot layer followed by their thermal decomposition on soot surface forming layer of pyrocarbon at forming of layer of pyrocarbon and activation of material compacted by pyrocarbon at temperature of 800-900°C and unloading of finished product. Granulated furnace black at specific surface of 10-30 m2/g and adsorption rate of 95-115 ml/100 g is used as backing for compacting with pyrocarbon. Then, product is subjected to activation for obtaining total volume of pores of 0.2-1.7 cm3/g. Black is compacted by pyrocarbon at two stages: at first stage, granulated black is compacted to bulk density of 0.5-0.7 g/cm3, after which material is cooled down and screened at separation of fraction of granules of 1.6-3.5 mm; at second stage, this fraction is subjected to repeated pyrolytic compacting to bulk density of granules of 0.9-1.1 g/cm3.

EFFECT: enhanced economical efficiency; increased productivity of process.

3 ex

FIELD: organic synthesis catalysts.

SUBSTANCE: invention relates to methods of preparing catalysts based on sulfurized styrene/divinylbenzene copolymer and thermoplastic polymer material, which are used in processes for preparing alkyl tert-alkyl ethers, hydration of olefins, dehydration of alcohols, preparation of esters, and the like. Invention provides molded ionite catalyst consisted of sulfurized styrene/divinylbenzene copolymer in the form of mixture of powdered copolymers with macroporous and gel structure and, as thermoplastic material, propylene polymers and propylene/ethylene copolymers. Preparation of catalyst is accomplished by extrusion at temperature of heating extruder cylinder 140-200°C and temperature of forming head equal to temperature of the last heated zone of heating cylinder.

EFFECT: increased catalytic activity.

10 cl, 3 tbl, 15 ex

FIELD: alternative fuel production and catalysts.

SUBSTANCE: invention relates to (i) generation of synthesis gas useful in large-scale chemical processes via catalytic conversion of hydrocarbons in presence of oxygen-containing components and to (ii) catalysts used in this process. Catalyst represents composite including mixed oxide, simple oxide, transition element and/or precious element, carrier composed of alumina-based ceramic matrix, and a material consisting of coarse particles or aggregates of particles dispersed throughout the matrix. Catalyst has system of parallel and/or crossing channels. Catalyst preparation method and synthesis gas generation method utilizing indicated catalyst are as well described.

EFFECT: enabled preparation of cellular-structure catalyst with high specific surface area, which is effective at small contact times in reaction of selective catalytic oxidation of hydrocarbons.

6 cl, 2 tbl, 16 ex

FIELD: petrochemical process catalysts.

SUBSTANCE: catalyst constitutes cements formed during heat treatment and depicted by general formula MeO·nAl2O3, where Me is at least one group IIA element and n is number from 1.0 to 6.0, containing modifying component selected from at least one oxide of magnesium, strontium, copper, zinc, indium, chromium, manganese, and strengthening additive: boron and/or phosphorus oxide. The following proportions of components are used, wt %: MeO 10.0-40.0, modifying component 1.0-5.0, boron and/or phosphorus oxide 0.5-5.0, and alumina - the balance. Catalyst is prepared by dry mixing of one group IIA element compounds, aluminum compounds, and strengthening additive followed by mechanochemical treatment on vibromill, molding of catalyst paste, drying, and calcination at 600-1200°C. Modifying additive is incorporated into catalyst by impregnation and succeeding calcination. Method of pyrolysis of hydrocarbon feedstock producing C2-C4-olefins is also described.

EFFECT: increased yield of lower olefins.

3 cl, 2 tbl, 18 ex

FIELD: supported catalysts.

SUBSTANCE: invention claims a method for preparation of catalyst using precious or group VIII metal, which comprises treatment of carrier and impregnation thereof with salt of indicated metal performed at working pressure and temperature over a period of time equal to or longer than time corresponding most loss of catalyst metal. According to invention, treated carrier is first washed with steam condensate to entirely remove ions or particles of substances constituted reaction mixture, whereupon carrier is dried at 110-130oC to residual moisture no higher than 1%.

EFFECT: achieved additional chemical activation of catalyst, reduced loss of precious metal from surface of carrier, and considerably increased lifetime.

5 cl, 9 ex

FIELD: petrochemical process catalysts.

SUBSTANCE: group of inventions relates to conversion of hydrocarbons using micro-mesoporous-structure catalysts. A hydrocarbon conversion process is provided involving bringing hydrocarbon raw material, under hydrocarbon conversion conditions, into contact with micro-mesoporous-structure catalyst containing microporous crystalline zeolite-structure silicates composed of T2O3(10-1000)SiO2, wherein T represents elements selected from group III p-elements and group IV-VIII d-elements, and mixture thereof, micro-mesoporous structure being characterized by micropore fraction between 0.03 and 0.40 and mesopore fraction between 0.60 and 0.97. Catalyst is prepared by suspending microporous zeolite-structure crystalline silicates having above composition in alkali solution with hydroxide ion concentration 0.2-1.5 mole/L until residual content of zeolite phase in suspension 3 to 40% is achieved. Thereafter, cationic surfactant in the form of quaternary alkylammonium of general formula CnH2n+1(CH3)3NAn (where n=12-18, An is Cl, Br, HSO4-) is added to resulting silicate solution suspension and then acid is added formation of gel with pH 7.5-9.0. Gel is then subjected to hydrothermal treatment at 100-150°C at atmospheric pressure or in autoclave during 10 to 72 h to produce finished product.

EFFECT: enlarged assortment of hydrocarbons and increased selectivity of formation thereof.

16 cl, 2 dwg, 2 tbl

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