Method for hydrogenation of vegetable oil and distilled fatty acid
FIELD: oil and fat industry and technology.
SUBSTANCE: invention relates to an improved method for hydrogenation of vegetable oils and distilled fatty acids. Method involves the hydrogenation reaction that is carried out on a catalyst stationary layer representing crystallites of active palladium applied on surface of carbonic material wherein mesoporous graphite-like material is used as carbonic material with granules size 0.5-6.0 mm but preferably 3.0-6.0 mm, specific surface 100-450 m2/g, average size of mesopores in the range from 40 to 400 Å, total volume of pores 0.2-0.6 cm3/g and part of mesopores in the total volume of pores 0.6, not less. Palladium crystallites in volume of carbonic material are distributed by so manner that the distribution maximum values of active component are in distance from external granule surface corresponding to 1-30% of its radius and in the content of applied palladium in the range from 0.5 to 2.0 wt.-%. Invention provides the high hydrogenation rate of raw in production of technical sorts of hydrogenated fats and high stability of product.
EFFECT: improved method of hydrogenation.
2 cl, 1 dwg, 3 tbl, 16 ex
The invention relates to the oil industry, and in particular to a method of hydrogenation of vegetable oils and distilled fatty acids (DIC), and can be used in the food, perfume, petrochemical and refining industries.
The number of known methods of hydrogenation of oils and fats and free fatty acids in the presence of catalysts based on transition metals Mo, W, Rh, Ir, Ru, Os, Ti, Re, Fe, Co, Ni, Pd, Pt, Cu, Ag, Au, Zn, Ga, etc. (J.I.Gray and L.F.Russell, J.Am.Oil Chemists Soc., v.56 (1979) 36-44). In this series, the most widespread methods of hydrogenation with the participation of Ni-containing catalysts. However, Nickel system inferior to the activity of palladium catalysts in the presence of which requires a degree of hydrogenation of vegetable oils and JK is achieved, ceteris paribus, at lower temperatures and pressures.
The hydrogenation process with the participation of such catalysts is carried out mainly in periodic mode using a suspended catalyst or in a continuous mode with a fixed catalyst bed. In the first case the synthesis of the hydrogenated fat is carried out in a temperature range 80-250°With at atmospheric or elevated pressure by means of a flow of hydrogen into the suspension of the powder catalyst (fraction of from 1 to 20 μm) in oil or GC. This mode makes it katal is the congestion a number of additional requirements, associated with the nature of their operation. Powdered catalyst must be easily separated (filtered) from the reaction products and to have good properties from the point of view of reuse. In the second case, the hydrogenation is carried out in a column type reactor at elevated hydrogen pressure up to 30 MPa and temperatures 90-250°passing the reagents from the bottom up through a fixed bed of granular catalyst (fraction of 0.5-15 mm). Catalysts in a fixed bed in addition to high efficiency (under "efficiency" refers to such process parameters as the activity and stability of catalyst while maintaining consumer properties of the product) must have high strength and low hydrodynamic resistance of the catalyst layer to the flow of the reactants.
The present invention provides a method of processing vegetable oils and GC in continuous mode with participation deposited on a carbon substrate granular palladium catalyst.
The known method [US 4479902, SS 3/11M, 30.10.1984], in which the continuous hydrogenation of vegetable oils is performed on Pd or Pt catalysts deposited on TiO2with the metal content of 0.1 wt.% at a temperature of 150-250°C, a hydrogen pressure from atmospheric up to 14 ATM. The media is a spherical pellets or extrudate is the size of about 1.6 mm Feature of the proposed method is the preparation of TiO2the method of deposition, which provides a sufficiently high specific surface area of 130 m2/year of the disadvantages of the method include the low reaction rate and a low degree of hydrogenation of double bonds. So, in optimal conditions, the hydrogenation of soybean oil in a flowing mode in the presence of 0.1% Pd/C leads to a product with iodine absorption number (IC) 97,9.
In the patent [US 5234883, B01J 21/06, 10.08.1993] the curing of unsaturated fatty acids is carried out on the catalyst with a high content of palladium (0.5 to 10 wt.%; the particle size of the metal 5-50 nm). The method is used as a catalyst carrier - TiO2obtained by molding a primary particle size 20 nm, with the following distribution of granule sizes: <0.5 mm - 29%, 0.5-1.0 mm - 32%, >1 mm - 39%. The peculiarity of this method is the preparation of the primary particles of the medium TiO2pyrogenic method, which provides a lower specific surface area of 50 m2/, the Catalyst has a low catalytic activity, presumably due to low specific surface of the carrier.
The authors of the patent [FR 2175223, SS 53/00, B01J 23/00, 19.10.1973] for the continuous method of hydrogenation of unsaturated fatty acids in order to obtain a product is below 10 or 20 offers the catalyst Pd/α - Al2O3with the contents fell down the adiya 0.5-5.0 wt.%. The carrier is molded in the form of tablets (3,2×3.2 mm) or extrudates (1,6×3.2 mm). The hydrogenation conditions: temperature 93-232°C, a hydrogen pressure of from 6.9 to 69 ATM, the ratio of hydrogen/fatty acid 1:1 to 20:1, supply of fatty acids 0.1-2 l/h per 1 liter of the catalyst. In contrast to commonly used media γ-Al2About3that can interact with fatty acids, giving aluminum compounds that block the active centers of the metal contaminate the catalyst and the product and make it difficult for the allocation of precious metal in pure form during regeneration α-Al2About3more inert. However, the catalyst Pd/α - Al2O3shows high activity at high hydrogen pressures (>21 ATM), even in these harsh conditions is the rapid deactivation of the catalyst, which is caused by blocking of active sites for adsorption of oil contains impurities of sodium soap and polar phosphatides on the hydrophilic surface of the aluminum oxide.
The known method [SA 1157844, SS 3/12, B01J 23/44, 29.11.1983] continuous curing fatty acids and vegetable oils in the presence of a palladium catalyst deposited on activated carbon with a Pd content of 0.5 to 3.0 wt.% and the size of the carrier extrudates 3×5 mm hydrogenation Conditions: 80-250°C, a hydrogen pressure of 0.5 to 50 ATM. This catalyst method is n when the volumetric feed rate of the distilled fatty acids 0.2 h -1derived from beef fat, reduce initial value is from 58 to 0.2 to 0.7 at a temperature of 190°and a hydrogen pressure of 25 ATM. The increase in feed rate GC to 0.6 h-1leads to increased iodine number of up to 2.5 and 3.3. However, in practice, when using the catalyst for hydrogenation of real raw material efficiency is much lower. To maintain the required degree of hydrogenation is necessary to introduce additional costly purification step GC or significantly reduce feed rate GC. Thus, this method is economically disadvantageous for use in industrial scale.
The closest technical solution to the claimed method is hydrogenation of vegetable oils and GC using catalyst proposed by the authors of the patent [EN 2056939, B01J 23/44, 27.03.1996] for the disproportionation of rosin (prototype), according to which the catalyst contains 1.5 to 2.5 wt.% palladium on a carbon carrier. While palladium is concentrated in the active layer of a thickness of 10-50 μm from the outer surface of the granules. The palladium particles have a preferred size of 2-8 nm and localized in the pores of the support size of 3-15 nm. The catalyst was prepared by deposition of palladium on granular media from aqueous palladium nitrate solution with a concentration of free nitric sour is s 6:1-1:1 (molar) with respect to palladium, dried in a current of air at 110-130°C. the Decomposition of deposited palladium nitrate is carried out in a current of inert gas at 200 to 300°and restore in hydrogen at 150-250°C.
In the example in the prototype examples, the catalysts were prepared on a carbon carrier with the following characteristics: grain size 1-3 mm, specific surface area by nitrogen adsorption - 400 m2/g, a bulk density of 0.6 kg/DM3total pore volume (capacity) - 0.6 cm3/g, predominant pore size is 4-10 nm, the ash content of 0.8 wt.%, abrasion - 0.1%/min
Catalysts prepared by this method exhibit high efficiency in the processes of intra - and intermolecular redistribution of hydrogen in the high-viscosity substrates, in particular, during the disproportionation part rosin and abietic other resin acids. We have shown that when in flow mode liquid-phase process of hydrogenation of vegetable oils and JC as a stationary layer can be used granulated catalysts prepared by this method.
The disadvantages of this method are lower performance in terms of a mass supported palladium and high hydrodynamic resistance in the reaction column of the layer of catalyst stream reagent the century
The invention solves the problem of efficient processing in a flowing mode of vegetable oils and GC cooked in a special way granulated palladium catalyst.
The task is solved by a method of hydrogenation of vegetable oils and GC on a stationary catalyst bed, representing the crystallites of catalytically active palladium deposited on the surface of the carbon material as a carbon material is used mesoporous graphite-like material with a grain size of 0.5-6.0 mm, preferably 3.0 to 6.0 mm, a specific surface area of 100-450 m2/g, with an average size of mesopores in the range of from 40 to 400 Åtotal pore volume of 0.2-0.6 cm3/g and the proportion of mesopores in the total volume of pores of not less than 0.6, in which the crystallites of palladium in the amount of the carbon material granules are distributed so that the maxima of the distribution of the active component was at a distance from the outer surface of the granules corresponding to 1-30% of its radius, when the content of supported palladium in the range from 0.5 to 2.0 wt.%. In such catalysts in obtaining food and technical summary : modified compositions obtained implements a higher degree of utilization of the active component; however, they have an increased service life. The increase in the thickness of the active layer leads to performance degradation of the catalyst due to the strengthening of the WPPT is usinig braking catalytic process in the depth of the pellets. When it was found that increasing the concentration of deposited Pd>1.5 wt.% in such catalysts, when these costs for raw materials leading to increased consumption by palladium. The decrease in the concentration of Pd<0.5 wt.% to obtain hydrogenated fat necessary quality job requires low loads on raw, which makes the use of such a catalyst ineffective. Hydrogenation of vegetable oils and JK exercise on a stationary layer of the above-described catalyst at a temperature of 140-210°C, the hydrogen pressure is from 2 to 12 ATM and the flow of raw materials from 100 to 1500 g/(kg)CT·h).
As the carbon materials can act as carriers prepared by heat treatment of plastics, as well as synthesized according to a special technology of gaseous hydrocarbons (V.A.Likholobov et al., React. Kin. Cat. Lett., v.54, 2 (1995) 381-411), namely, Sibunit, catalytic filamentous carbon (CEF) and various composites on their basis, for which Vmeso/VΣis ≥0,6. The size of granules such carriers obtained by known technologies, as a rule, does not exceed 3 mm Catalysts prepared on their basis, during operation in the reactor column type when passing through the layer of catalyst such viscous substrates, as oil and JC have a high hydrodynamic resistance. Indeed, presented at the cher the annual evaluation of the mathematical calculations of the values of the dynamic component of the hydraulic resistance of the catalyst layer for spherical particles on industrial alloy Ni-Al catalyst (⊘ cf.=11.8 mm) in the column hydrogenation under the following process parameters: rapeseed oil - consumption 2,5 t/h, the hydrogen flow rate 160 l/s, pressure in the column (medium) - 6 ATM, the temperature - 180°To show that with decreasing the grain size of the catalyst is observed exponential increase of the resistance of the catalyst layer to the flow of oil. When using a granule size of less than 3.0 mm, the ratio of pressure drop across the layer is such that you may experience problems with pumping the feedstock through the catalyst bed. Therefore, in the present invention as applied to the conditions of hydrogenation of oils and JK as carriers of the catalyst are offered granules are larger in size.
These parameters provide high performance in terms of a mass supported palladium in the production of summary : modified compositions obtained low hydrodynamic resistance in the reaction column of catalyst layer flow of reagents, as well as increased stability of the catalyst (longer service life).
Distinctive features of the present invention in comparison with the prototype are:
1) the scope of the catalyst, including its use in the process of hydrogenation of vegetable oils and fats. The hydrogenation process is performed on a stationary catalyst bed at a temperature of 140-210°C, the hydrogen pressure is from 2 to 12 ATM and the flow of raw materials from 100 to 1500 g/(kg) CT·h);
2) the low content of the active component in the catalyst;
3) using as a carrier of porous carbon material with a share of mesopores in the total pore volume (Vmeso/VΣ) not less than 0.6 and bóthe great size of the granules.
Below are examples 1-16, illustrating the claimed method. Of these examples 14 and 15 are given for comparison and example 12 is shown as a prototype. Data on physico-chemical and textural properties of the carriers used for the preparation of the catalysts are shown in table 1. Table 2 shows the composition and properties of the catalysts used in the examples below.
In a tubular reactor made of stainless steel (internal ⊘=25 mm) load of 14 g of the catalyst Pd/Sib (No. 1; hereinafter specified No. of catalysts from table 2) with a palladium content of 0.5 wt.%. The reactor is hermetically connected to the system. The system is rinsed with nitrogen, then with hydrogen to increase the hydrogen pressure in the system to work. In control panel, set the desired temperature of the reaction and include heating furnace. The capacity to download raw rapeseed oil (IC 110,9 g I2/100 g, the title of 10.2°, an acid number of 0.3 mg KOH/g). Before dosing into the reactor rapeseed oil heated to 60°With capacity rinsed with nitrogen and establish the working pressure is of hydrogen.
The hydrogenation process is carried out in continuous mode in a stationary catalyst bed at a temperature 170-182°C, a hydrogen pressure of 6 ATM and the consumption of raw materials 686 g/(kg)CT·h). When this mixture of hydrogen and oil is carried out in a special way at the bottom of the reactor. The resulting mixture passed through the catalyst bed from the bottom up. Sampling for quality analysis of the product produced every 2-3 hours
Determination of the titer of the obtained hydrogenated fat performed by standard methods (Bezzubov, L.P. Chemistry of fats. M: Food promyshlennosti. 1976, s). Iodine number is determined by titration of a sample of the product solution of sodium bromide and bromine in methyl alcohol according to the method of the Kaufman Guide to research methods, chemical control and accounting of production in the oil industry. Leningrad. 1982, vol. 1, s).
Analytical quality data hydrogenated fat obtained in this way are presented in table 3.
The process is carried out as in example 1, but is used as raw material GC (IC of 94.5 g I2/100 g, the title 28,4°, acid number 195,4 mg KOH/g). Before dosing into the reactor JK heated to 90°C. the Parameters of the hydrogenation process and the characteristics of the resulting summary : modified compositions obtained are shown in table 3.
Examples 3-4. The process of hydrogenation of rapeseed oil carried out as in example 1, but with IP is the use of catalysts Pd/Sib (No. 2) and Pd/Sib (No. 9), respectively. The parameters of the hydrogenation process and the characteristics of the resulting summary : modified compositions obtained are shown in table 3.
The process of hydrogenation JK carried out in example 2 using the catalyst Pd/Sib (No. 2-8), Pd/FAS (No. 10), Pd/CEF (No. 11) and Pd/Sib (No. 9, 12). The parameters of the hydrogenation process and the characteristics of the resulting summary : modified compositions obtained are shown in table 3.
As can be seen from the examples, drawings and tables, the present invention allows to provide for production of summary : modified compositions obtained low hydrodynamic resistance in the reaction column of catalyst layer flow of reagents, as well as the high productivity of the process in terms of a mass supported palladium. Thus, the proposed method solves the problem of efficient processing in a flowing mode of vegetable oils and GC.
|The main characteristics of granular porous carbon materials|
|The origin (source)||hydrocarbons||the furfural||hydrocarbons||hydrocarbons|
|Vmicro 2)cm3/g||0,015||mean HDI of 0.531||0,010||0,010|
|Vmeso 3)cm3/g||0,665||0,442||0,310||to 0.480|
|1)Sbeats(m2/g) specific surface area by BET. The surface area was calculated from plot isotherms, where R/R0=0.05-0.20; size of area of the nitrogen molecule in the completed monomolecular layer was assumed to be equal to ω=0.162 nm2;|
2)Vmicro(cm3/g) micropore volume. Calculated using the comparative method in areas of the isotherm corresponding to the region between the filling of micropores and the beginning of the capillary condensation; the value of Vmicrocorresponds to the volume of ultramicro and Supermicro, then eats the volume of micropores smaller than 20 Å ;
3)Vmeso(cm3/g) = VΣ-Vmicro;
4)VΣ(cm3/g) pore volume of less than 5000 Å. Calculated from nitrogen adsorption at P/P0=0.98.
|The composition and properties of catalysts|
|no catalyst||Catalyst||The Pd content, wt.%||Dispersion, CO/Pd1)||Δcf., mkm,2)|
|1)The dispersion (D) of the obtained catalysts determined by pulse method by chemisorption of CO at 20°C. the Value of D calculated on the basis of the stoichiometry of CO/Pds=1:1 (mol/mol).|
2)Electron microprobe granules of the catalyst is carried out by scanning slice granules in diameter using a MAR-3. Δcf.- the arithmetic mean of parameter Δcharacterizing the thickness of the active layer in μm at 1/2 peak height distribution of the metal in the surface layer of the granules.
|Feature summary : modified compositions obtained obtained on palladium catalysts according to examples 1 to 16|
|Example No.||The composition of the catalyst||Raw materials||T °||PH2kgf/cm2||Reaction time, hours||The feed rate, g/HR||Eat a CR-TA, g/(kg)CT·h)||Eat a CR-TA, g/(gPd·h)||The title °||IC, g I2/100 g|
|1||0.5%Pd/Sib (No. 1)||oil||170-182||6||15||9,6||686||137,1||57,2-59,3|
|2||0.5%Pd/Sib (No. 1)||GK||150-162||6-8||30||4,3||307||61,4||57,5 is 60.5||6,0-9,1|
|3||0.5%Pd/Sib (No. 2)||oil||179-183||6||101||10,9||779||155,7||59,2 is 60.5|
|4||0.5%Pd/Sib (No. 9)||oil||179-189||6||15||10.7||764||152,9||62,2-64,0|
|5||0.5%Pd/Sib (No. 2)||GK||174-177||6||20||of 5.4||386||77,1||58,0-60,0|
|6||0.5%Pd/Sib (No. 2)||GK||214-224||6||22||6,2||443||88,6||56,5-58,0|
|7||05%Pd/Sib (No. 3)||GK||144-160||6-8||91||5,6||400||80,0||to 57.0-60.0 sec|
|8||0.5%Pd/Sib. 1 (No. 4)||GK||149-160||6||15||4,3||307||61,4||of 57.5-60.0 sec|
|9||0.5%Pd/Sib (No. 5)||GK||148-162||6-8||15||5,2||371||74,3||to 57.0-60.0 sec|
|10||0.5%Pd/Sib (No. 6)||GK||144-160||6-8||15||6,5||464||92,9||57,0-59,0|
|11||1.0%Pd/Sib (No. 7)||GK||158-165 (in Russian)||6-8||30||5,2||371||37,1||57,5-59,0|
|121)||2.0%Pd/Sib (No. 8)||GK||154-157||6-8||30||8,6||614||30,7||57,5-60,2||6,2-9,5|
|13||0.5%Pd/Sib (No. 9)||GK||199-204||6||31||6,2||443||88,6|
|142)||0.5%Pd/FAS (No. 10)||GK||148-157||6||15||4,8||343||68,6||73,5-75,7|
|152)||0.5%Pd/CEF (No. 11)||GK||155-163||6||16||6,1||436||87,1||57,2-59,3|
|16||1.0%Pd/Sib (No. 12)||GK||161-196||6-10||159||a 4.9||350||35,0||57,0-59,0||6,1-15,2|
1. The method of hydrogenation of vegetable oils and distilled fatty acids, characterized in that the hydrogenation is conducted at a stationary catalyst bed, representing the crystallites of catalytically active palladium deposited on the surface of the carbon material as a carbon material is used mesoporous graphite-like material with a grain size of 0.5-6.0 mm, preferably 3.0 to 6.0 mm, a specific surface area of 100-450 m2/g, with an average size of mesopores in the range of from 40 to 400 Åtotal pore volume of 0.2-0.6 cm3/g and the proportion of mesopores in General, the volume of pores of not less than 0.6, in which the crystallites of palladium in the amount of the carbon material granules are distributed so that the maxima of the distribution of the active component was at a distance from the outer surface of the granules corresponding to 1-30% of its radius, when the content of supported palladium in the range from 0.5 to 2.0 wt.%.
2. The method according to claim 1, characterized in that the hydrogenation of vegetable oils and distilled fatty acids of the catalyst is carried out at a temperature of 140-210°C, the hydrogen pressure is from 2 to 12 ATM and the flow of raw materials from 100 to 1500 g/(kg)CT·h).
FIELD: fat-and-oil industry.
SUBSTANCE: fat base for production of margarine is obtained by liquid-phase hydrogenation of vegetable oils with hydrogen in presence of repetitively reused palladium catalyst supported by carbon carrier, particularly nano-cluster palladium on nano-carbon cluster material. Process is carried out at 60-90°C. Method allows content of trans-isomers in hydrogenation products as well as iodine number of products to be lowered.
EFFECT: improved quality of products and essentially reduced power consumption.
1 tbl, 3 ex
FIELD: inorganic synthesis catalysts.
SUBSTANCE: invention relates to catalytic elements including ceramic contact of regular honeycomb structure for heterogeneous high-temperature reactions, e.g. ammonia conversion, and can be used in production of nitric acid, hydrocyanic acid, and hydroxylamine sulfate. Described is catalytic element for heterogeneous high-temperature reactions comprising two-step catalytic system consisting of ceramic contact of regular honeycomb structure made in the form of at least one bed constituted by (i) separate prisms with honeycomb canals connected by side faces with gap and (ii) platinoid grids, ratio of diameter of unit honeycomb canal to diameter of wire, from which platinoid grids are made, being below 20.
EFFECT: increased degree of conversion and degree of trapping of platinum, and prolonged lifetime of grids.
5 cl, 6 ex
FIELD: disproportionation reaction catalysts.
SUBSTANCE: invention relates to Fischer-Tropsch catalyst containing cobalt and zinc, to a method for preparation thereof, and to Fischer-Tropsch process. Catalyst according to invention containing co-precipitated cobalt and zinc particles, which are characterized by volume-average size below 150 μm and particle size distribution wherein at least 90% of the catalyst particle volume is occupied by particles having size between 0.4 and 2.5 times that of the average particle size and wherein zinc/cobalt atomic ratio within a range of 40 to 0.1. Catalyst is prepared by introducing acid solution containing zinc and cobalt ions at summary concentration 0.1 to 5 mole/L and alkali solution to reactor containing aqueous medium wherein acid solution and alkali solution come into contact with each other in aqueous medium at pH 4-9 (deviating by at most 0.2 pH units) at stirring with a speed determined by supplied power between 1 and 300 kW/L aqueous medium and temperature from 15 to 75°C. Resulting cobalt and zinc-including precipitate separated from aqueous medium, dried, and further treated to produce desired catalyst. Employment of catalyst in Fischer-Tropsch process is likewise described.
EFFECT: enhanced strength and separation properties suitable for Fischer-Tropsch process.
13 cl, 2 dwg, 1 tbl, 5 ex
FIELD: exhaust gas afterburning means.
SUBSTANCE: invention relates to catalytic neutralizer for treating internal combustion engine exhausted gases. Proposed catalyst is composed of catalytically active coating on inert ceramic or metallic honeycomb structure, wherein coating contains at least one platinum group metal selected from series including platinum, palladium, rhodium, and iridium on fine-grain supporting oxide material, said supporting oxide material representing essentially nonporous silica-based material including aggregates of essentially spherical primary particles 7 to 60 nm in diameter, while pH of 4% water dispersion of indicated material is below 6.
EFFECT: increased catalyst activity and imparted sufficient resistance to aggressive sulfur-containing components.
27 cl, 2 dwg, 7 tbl, 6 ex
FIELD: chemical industry; methods of manufacture of the building structures.
SUBSTANCE: the invention is pertaining to the field of the chemical industry, in particular, to production of the nitric acid, nitric fertilizers, the cyanhydric acid, the nitrites and nitrates and to other productions of chemical products, where the flow sheet of production provides for the catalytic conversion of ammonia up to the nitrogen oxides with usage of the platinoid mesh catalytic agents. The platinoid mesh catalytic agent formed in the form of the catalytic package produced out of the layer-by-layer stacked wire catalytic meshes and weaved out of the wires with the diameter of 0.06-0.1 mm consisting of the alloys of platinum with rhodium, palladium, ruthenium and other metals of the platinum group differs that the catalytic package consists of two different in the geometry of the braiding types of the meshes sequentially alternating in the height of the package. At that the geometry of the braiding of the first type of the catalytic meshes is characterized by the number of the wires interlacing per 1 cm2 in the interval of 1024-450, and the geometry of the braiding of the second type of the catalytic meshes is characterized by the number of the wires interlacing per 1 cm2 in the interval of 400-200. The technical result of the invention is the increased conversion of ammonia and the decreased share of the platinoids included in the mesh catalytic agent production processes providing for the catalytic conversion of ammonia in the flow sheet of the chemical goods production.
EFFECT: the invention ensures the increased conversion of ammonia and the decreased share of the platinoids included in the mesh catalytic agent production processes providing for the catalytic conversion of ammonia in the flow sheet of the chemical goods production.
FIELD: composition and structure of composite metal semiconductor meso-porous materials; titanium-dioxide-based catalyst for photo-chemical reactions.
SUBSTANCE: proposed catalyst is meso-porous titanium-dioxide-based material containing crystalline phase of anatase in the amount no less than 30 mass-% and nickel in the amount no less than 2 mass-%; material has porous structure at average diameter of pores from 2 to 16 nm and specific surface no less than 70 m2/g; as catalyst of photo-chemical reaction of liberation of hydrogen from aqua-alcohol mixtures, it ensures quantum reaction yield from 0.09 to 0.13. Method of production of such catalyst includes introduction of precursor - titanium tetraalkoxyde and template of organic nature, holding reagent mixture till final molding of three-dimensional structure from it at successive stages of forming sol, then gel, separation of reaction product and treatment of this product till removal of template; process is carried out in aqua-alcohol solvent containing no more than 7 mass-% of water; at least one of ligands is introduced into solvent as template; ligand is selected from group of macro-cyclic compounds containing no less than four atoms of oxygen and/or from complexes of said macro-cyclic compounds with ions of metals selected from alkaline or alkaline-earth metals or F-metals containing lithium, potassium, sodium, rubidium, cesium, magnesium, calcium, strontium, barium, lanthanum and cerium; mixture is stirred before forming of sol maintaining its temperature not above 35°C till final molding of three-dimensional structure from reagent mixture; mixture is held in open reservoir at the same temperature at free access of water vapor; after removal of template from three-dimensional structure, mixture is first treated with nickel salt solution during period of time sufficient for withdrawal of nickel ions from solution by pores of structure, after which is it kept in hydrogen-containing medium during period of time sufficient for reduction of nickel ions in pores of structure to metallic nickel.
EFFECT: enhanced sorption and photo-catalytic parameters; reproducibility of catalyst properties.
7 cl, 68 ex
FIELD: organic chemistry, chemical technology.
SUBSTANCE: invention relates to a method for liquid-phase catalytic alkylation of aromatic amines. Method involves alkylation reaction of aromatic amines in the presence of hydrogen and lower alcohols at temperature 50-70°C on a heterogeneous catalyst. The distinctive specificity of method represents alkylation of amine with formaldehyde solution in reactor with reaction zone filled with catalyst consisting of aluminum oxide-base block high-porous cellular carrier with porosity value 7-95%, not less, and palladium as an active component with the mass content = 1.3-2%. As a rule, in the alkylation process catalyst prepared by impregnation of block high-porous cellular carrier with palladium salts treated preliminary in the constant magnetic field is used. Usually, in the case of alkylation of aniline and for preferential synthesis of monomethylaniline the molar ratio aniline to formaldehyde solution = 1.6:(1.1-1.6) is used. Proposed method as compared with the nearest analog in the case of alkylation of aniline provides preparing monomethylaniline mainly, to decrease the content of palladium as an active component in catalyst and to decrease the reaction pressure and hydraulic resistance of catalytic layer also. Invention can be used in producing antiknock additives to motor fuels (gasolines).
EFFECT: improved alkylation method.
3 cl, 4 ex
FIELD: catalyst preparation methods.
SUBSTANCE: invention relates to a method for preparing catalyst and to catalyst no honeycomb-structure block ceramic and metallic carrier. Preparation procedure includes preliminarily calcining inert honeycomb block carrier and simultaneously applying onto its surface intermediate coating composed of modified alumina and active phase of one or several platinum group metals from water-alcohol suspension containing, wt %: boehmite 15-30, aluminum nitrate 1-2, cerium nitrate 4-8, 25% ammonium hydroxide solution 10-20, one or several precipitate group metal salts (calculated as metals) 0.020-0.052, water-to-alcohol weight ratio being 1:5 to 1:10; drying; and reduction. Thus prepared catalyst has following characteristics: specific coating area 100-200 m2/g, Al2O3 content 5-13%, CeO2 content 0.5-1,3%, active phase (on conversion to platinum group metals) 0.12-0.26%.
EFFECT: simplified technology due to reduced number of stages, accelerated operation, and high-efficiency catalyst.
5 cl, 1 tbl, 10 ex
FIELD: catalyst preparation methods.
SUBSTANCE: method involves preparing porous carrier and forming catalyst layer by impregnation of carrier with aqueous solution of transition group metal salts followed by drying and calcination. Porous catalyst carrier is a porous substrate of organic polymer material: polyurethane or polypropylene, which is dipped into aqueous suspension of powdered metal selected from metals having magnetic susceptibility χ from 3.6·106 to 150·106 Gs·e/g: iron, cobalt, chromium, nickel, or alloys thereof, or vanadium and polyvinylacetate glue as binder until leaving of air from substrate is completed, after which carrier blank is dried at ambient temperature and then fired at 750°C in vacuum oven and caked at 900-1300°C. Caked blank is molded and then subjected to rolling of outside surface to produce carrier having variable-density structure with density maximum located on emitting area. Formation of catalyst layer is achieved by multiple impregnations of the carrier with aqueous solution of acetates or sulfates of transition group metals: iron, cobalt, chromium, nickel, or alloys thereof in alternative order with dryings at ambient temperature and calcinations to produced catalyst bed 50-80 μm in thickness. In another embodiment of invention, formation of catalyst layer on carrier is accomplished by placing carrier in oven followed by forcing transition group metal carbonate vapors into oven for 60-120 min while gradually raising oven temperature to 850°C until layer of catalyst is grown up to its thickness 50-80 μm.
EFFECT: improved quality of catalyst and reduced its hydrodynamic resistance.
8 cl, 1 tbl, 3 ex
FIELD: organic chemistry, chemical technology.
SUBSTANCE: invention relates to technology for preparing caprolactam by the cyclization reaction of derivatives of aminocaproic acid. Method is carried out by cyclizing hydrolysis of compound chosen from the group comprising aminocaproic acid esters or amides, or their mixtures. The process is carried out in the presence of water, in vapor phase at temperature 200-450°C in the presence of a solid catalyst comprising of aluminum oxide that comprises at least one macroporosity with pores volume corresponding to pores with diameter above 500 Å taken in the concentration 5 ml/100 g of above. Preferably, the specific square of catalyst particles is above 10 m2/g and the total volume of pores is 10 ml/100 g or above wherein pores volume corresponds to pores with diameter above 500 Å is 10 ml/100 g or above. Invention provides improving the process indices due to the improved properties of the solid catalyst.
EFFECT: improved preparing method.
5 cl, 2 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: industrial organic synthesis catalysts.
SUBSTANCE: method of improving selectivity of highly selective epoxidation catalyst on support containing silver in amount at most 0.19 g per 1 m2 of the support surface area comprises bringing catalyst or catalyst precursor containing silver in cationic form into contact with oxygen-containing raw material at catalyst temperature above 250°C over a period of time more than 150 h, after which catalyst temperature is lowered to at most 250°C. Olefin epoxidation process comprises bringing above-described supported catalyst or catalyst precursor into contact with oxygen-containing raw material at catalyst temperature above 250°C over a period of time more than 150 h, after which catalyst temperature is lowered to at most 250°C and catalyst is brought into contact with raw material containing olefin and oxygen.
EFFECT: increased selectivity of catalyst.
12 cl, 3 tbl, 12 ex