The catalyst for aromatization of saturated hydrocarbons and the method of its preparation

 

(57) Abstract:



 

Same patents:

FIELD: heterogeneous catalysts.

SUBSTANCE: catalyst contains porous carrier, buffer layer, interphase layer, and catalytically active layer on the surface wherein carrier has average pore size from 1 to 1000 μm and is selected from foam, felt, and combination thereof. Buffer layer is located between carrier and interphase layer and the latter between catalytically active layer and buffer layer. Catalyst preparation process comprises precipitation of buffer layer from vapor phase onto porous carrier and precipitation of interphase layer onto buffer layer. Catalytic processes involving the catalyst and relevant apparatus are also described.

EFFECT: improved heat expansion coefficients, resistance to temperature variation, and reduced side reactions such as coking.

55 cl, 4 dwg

FIELD: physical or chemical processes and apparatus.

SUBSTANCE: method comprises saturating the initial gas mixture that is comprises agents to be oxidized with vapors of hydrogen peroxide. The photocatalyst is made of pure titanium dioxide that contains one or several transition metals.

EFFECT: expanded functional capabilities and enhanced efficiency.

7 cl, 2 dwg, 1 tbl, 11 ex

FIELD: petrochemical process catalysts.

SUBSTANCE: invention relates to catalytic methods of isomerizing n-butane into isobutane and provides catalyst constituted by catalytic complex of general formula MexOy*aAn-*bCnXmH2n+2-m, where Me represents group III and IV metal, x=1-2, y=2-3, An- oxygen-containing acid anion, a=0.01-0.2, b=0.01-0.1; CnXmH2n+2-m is polyhalogenated hydrocarbon wherein X is halogen selected from a series including F, Cl, Br, I, or any combination thereof, n=1-10, m=1-22, dispersed on porous carrier with average pore radius at least 500 nm and containing hydrogenation component. Method of preparing this catalyst is also disclosed wherein above-indicated catalytic complex is synthesized from polyhalogenated hydrocarbon CnXmH2n+2-m wherein X, n, and m are defined above, group III and IV metal oxide, and oxygen-containing acid anion, and dispersed on porous carrier with average pore radius at least 500 nm, hydrogenation component being introduced either preliminarily into carrier or together with catalytic complex. Process of isomerizing n-butane into isobutane utilizing above-defined catalyst is also described.

EFFECT: lowered butane isomerization process temperature and pressure and increased productivity of catalyst.

13 cl, 1 tbl, 24 ex

FIELD: petrochemical process catalysts.

SUBSTANCE: invention relates to catalytic methods of isomerizing n-paraffins and provides catalyst constituted by catalytic complex of general formula MexOy*aAn-*bCnXmH2n+2-m, where Me represents group III and IV metal, x=1-2, y=2-3, An- oxygen-containing acid anion, a=0.01-0.2, b=0.01-0.1; CnXmH2n+2-m is polyhalogenated hydrocarbon wherein X is halogen selected from a series including F, Cl, Br, I, or any combination thereof, n=1-10, m=1-22, dispersed on porous carrier with average pore radius at least 500 nm and containing hydrogenation component. Method of preparing this catalyst is also disclosed wherein above-indicated catalytic complex is synthesized from polyhalogenated hydrocarbon CnXmH2n+2-m wherein X, n, and m are defined above, group III and IV metal oxide, and oxygen-containing acid anion, and dispersed on porous carrier with average pore radius at least 500 nm, hydrogenation component being introduced either preliminarily into carrier or together with catalytic complex. Process of isomerizing n-paraffins utilizing above-defined catalyst is also described.

EFFECT: lowered isomerization process temperature and pressure and increased productivity of catalyst.

17 cl, 3 tbl, 25 ex

FIELD: petrochemical processes and catalysts.

SUBSTANCE: invention provides catalyst composed of heteropolyacid: phosphorotungstic acid and/or phosphoromolybdenic acid, at least one precious metal deposited on essentially inert inorganic amorphous or crystalline carrier selected from group including titanium dioxide, zirconium dioxide, aluminum oxide, and silicon carbide, which catalyst retains characteristic structure of heteropolyacid confirmed by oscillation frequencies of the order 985 and 1008 cm-1 recorded with the aid of laser combination scattering spectroscopy and which has specific surface area larger than 15 m2/g, from which surface area in pores 15 Å in diameter is excluded. Method of converting hydrocarbon feedstock containing C4-C24-paraffins in presence of above-defined catalyst is likewise described.

EFFECT: increased catalyst selectivity and enhanced hydrocarbon feedstock conversion.

5 cl, 7 tbl, 7 ex

FIELD: hydrogenation-dehydrogenation catalysts.

SUBSTANCE: invention concerns catalysts for dehydrogenation of C2-C5-alkanes into corresponding olefin hydrocarbons. Alumina-supported catalyst of invention contains 10-20% chromium oxide, 1-2% alkali metal compound, 0.5-2% zirconium oxide, and 0.03-2% promoter oxide selected from zinc, copper, and iron. Precursor of alumina support is aluminum oxide hydrate of formula Al2O3·nH2O, where n varies from 0.3 to 1.5.

EFFECT: increased mechanical strength and stability in paraffin dehydrogenation process.

9 cl, 1 dwg, 3 tbl, 7 ex

FIELD: industrial organic synthesis catalysts.

SUBSTANCE: process is effected in reactor containing compacted bed of supported catalyst including group VIII metal, in particular cobalt, said metal being partially present in its metallic form. Supported catalyst has, on its outside surface, catalytically active metal. Compacted bed is characterized by having hollow volume more than 50 vol % and specific surface area more than 10 cm2/cm3, which is calculated as total outside surface of particles divided by bed volume.

EFFECT: improved economical efficiency of process.

8 cl, 3 tbl, 7 ex

FIELD: industrial organic synthesis catalysts.

SUBSTANCE: invention relates to environmentally friendly processes for production of isoalkanes via gas-phase skeletal isomerization of linear alkanes in presence of catalyst. Invention provides catalyst for production of hexane isomers through skeletal isomerization of n-hexane, which catalyst contains sulfurized zirconium-aluminum dioxide supplemented by platinum and has concentration of Lewis acid sites on its surface 220-250 μmole/g. Catalyst is prepared by precipitation of combined zirconium-aluminum hydroxide from zirconium and aluminum nitrates followed by deposition of sulfate and calcination in air flow before further treatment with platinum salts. Hexane isomer production process in presence of above-defined cat is also described.

EFFECT: increased catalyst activity.

5 cl, 2 tbl, 6 ex

FIELD: catalyst preparation methods.

SUBSTANCE: catalyst containing crystalline anatase phase in amount at least 30% and nickel in amount 0.5 to 2% has porous structure with mean pore diameter 2 to 16 nm and specific surface at least 70 m2/g. When used to catalyze photochemical reaction of isolation of hydrogen from water-alcohol mixtures, it provides quantum yield of reaction 0.09-0.13. Preparation of titanium dioxide-based mesoporous material comprises adding titanium tetraalkoxide precursor and organic-nature template to aqueous-organic solvent, ageing reaction mixture to complete formation of spatial structure therefrom through consecutive sol and gel formation stages, separating reaction product, and processing it to remove template. Invention is characterized by that water-alcohol derivative contains no more than 7% water and template consists of at least one ligand selected from group of macrocyclic compounds, in particular oxa- and oxaazamacrocyclic compounds containing at least four oxygen atoms, and/or complexes of indicated macrocyclic compounds with metal ions selected from group of alkali metals or alkali-earth metal metals, or f-metals consisting, in particular, of lithium, potassium, sodium, rubidium, cesium, magnesium, calcium, strontium, barium, lanthanum, and cerium used in amounts from 0.001 to 0.2 mole per 1 mole precursor. Sol is formed by stirring reaction mixture at temperature not higher than 35°C. Once formation of spaced structure completed, mixture is held at the same temperature in open vessel to allow free access of water steam and, when template is removed from the mixture, mixture is first treated with nickel salt solution and then with alkali metal borohydride solution until metallic nickel is formed.

EFFECT: increased sorption and photocatalytic properties of catalyst and enabled reproducibility of its property complex.

7 cl, 68 ex

FIELD: catalyst preparation methods.

SUBSTANCE: invention proposes combination of protective layer against chlorine compounds and copper-containing catalyst bed. Protective layer is formed from molded members prepared from particles of led carbonate and/or basic led carbonate with weight-average particle size less than 10 μm. Catalytic reaction in presence of above-defined combination is also described.

EFFECT: prevented deactivation of copper-containing catalyst operated with process gas containing chlorine compounds.

11 cl, 3 tbl, 7 ex

FIELD: catalyst manufacture technology.

SUBSTANCE: invention relates to carbon monoxide-water steam conversion to form nitrogen-hydrogen mixture that can be used in ammonia synthesis. Preparation of catalyst comprises precipitation of iron hydroxide from iron nitrate solution with ammonia-containing precipitator, washing of iron hydroxide to remove nitrate ions, mixing with copper compound, granulation, and drying and calcination of granules. Invention is characterized by that iron hydroxide is mixed with copper and calcium oxides at molar ratio Fe2O3/CuO/CaO = 1:(0.03-0.2):(1.0-2.0), after which mechanical activation is performed. Resulting catalyst is 1.8-2.0-fold stronger and by 11.0-15.4% more active than prototype catalyst.

EFFECT: increased strength and catalytic activity.

1 tbl, 3 ex

FIELD: petrochemical processes.

SUBSTANCE: hydrocarbons are produced via contacting synthesis gas with catalytic composition consisting of mixture of iron-containing Fischer-Tropsch synthesis catalyst and acid component at elevated pressures and temperatures and specified iron-containing catalyst reduction conditions. Specifically, said iron component is a mixture of neodymium and cerium silicates at weight ratio between 1:9 and 9:1 and weight ratio of acid component to iron-containing catalyst ranges from 1:1 to 6:1.

EFFECT: increased selectivity and productivity of catalyst and reduced level of aromatic hydrocarbons in product.

3 cl, 1 tbl, 15 ex

FIELD: industrial inorganic synthesis catalysts.

SUBSTANCE: iron catalyst for ammonia synthesis is reduced via heating of nitrogen/hydrogen mixture to 300-350°C at pressure 0.3-10 MPa, passing it through first activated catalyst bed, which represents 0.2 to 13% of the total volume of catalyst charged into ammonia synthesis column, then through second non-activated iron oxides-based catalyst bed at elevated pressure, whereupon catalyst is aged, temperature and pressure are raised to 425-500°C at pressure 10-20 MPa and catalyst is finally aged to reduce non-activated catalyst bed. Above-mentioned upstream disposed first catalyst bed is low-temperature ammonia synthesis ruthenium catalyst deposited on catalytic carrier.

EFFECT: enhanced process efficiency.

2 cl, 1 tbl, 3 ex

FIELD: inorganic synthesis catalysts.

SUBSTANCE: passivation of ammonia synthesis catalyst is accomplished via consecutively treating reduced iron catalyst with oxidant at elevated temperatures and process flow rates. Treatment of catalyst with oxidant is commenced with water steam or steam/nitrogen mixture at 150-300°C while further elevating temperature by 50-200°C, after which temperature is lowered to 150-300°C, at which temperature water steam or steam/nitrogen mixture is supplemented by air and treatment of catalyst is continued with resulting mixture while elevating temperature by 50-200°C followed by reduction of catalyst temperature in this mixture to 150-300°C and cooling of catalyst with nitrogen/oxygen mixture at initial ratio not higher than 1:0.1 to temperature 30°C and lower until nitrogen/oxygen mixture gradually achieves pure air composition.

EFFECT: prevented self-inflammation of ammonia synthesis catalyst when being discharged from synthesis towers due to more full oxidation.

6 cl, 1 tbl, 5 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: catalyst preparation methods.

SUBSTANCE: invention relates to methods for preparing carbon monoxide-conversion catalysts used in production of hydrogen, nitrogen-hydrogen mixture, and other hydrogen-containing gases. According to first option, active catalyst component, i.e. iron compound, is precipitated from solution with precipitation reagent, whereupon precipitate is separated from mother liquor and washed to form catalyst mass, which is molded and subjected to heat treatment, re-washed, mixed with chromic anhydride and subjected to final heat treatment: at 280-420°C after molding or at 50-200°C before molding of catalyst mass. According to second option, iron compound is first mixed with promoting additives and cations of promoting additives are precipitated jointly with iron cations, resulting precipitate is separated from mother liquor, washed and subjected to heat treatment, re-washed, mixed with chromic anhydride and subjected to final heat treatment: at 280-420°C after molding or at 50-200°C before molding of catalyst mass. As iron compound in the first and second options, ferrous and ferric sulfates and, as precipitation reagent, carbonate salts or corresponding hydroxides are utilized. Promoting additives are selected from Cu, Mn, and Al or, in the second option, their mixture.

EFFECT: reduced content of sulfur in finished catalyst at the same catalyst activity.

3 cl, 1 tbl, 12 ex

FIELD: gas-treatment catalysts.

SUBSTANCE: supported catalysts are prepared via process of self-propagating thermal synthesis of active component from precursors, which are oxidants and reducers interacting under thermal synthesis conditions and being either in different compounds or combined in the same compound, after which both oxidant and reducer are applied onto support from their solutions, melts, or suspensions. Process is characterized by self-propagating thermal synthesis is conducted within volume of porous support, which is granulated or block-type γ-Al2O3 with specific surface 150-230 m2/g and active component precursors applied thereon. Thus obtained superfine oxide catalyst is appropriate to remove hydrocarbons, carbon oxides, and nitrogen from gas emissions.

EFFECT: developed rapid, moderately power-consuming, and environmentally safe process and increased catalyst activity.

4 cl, 1 dwg, 1 tbl, 16 ex

FIELD: hydrocarbon conversion processes.

SUBSTANCE: process consists in catalytic decomposition of hydrocarbon-containing gas at elevated temperature and pressure 1 to 40 atm, catalyst being reduced ferromagnetic cured product isolated by magnetic separation from ashes produced in coal combustion process at power stations. The catalytic product represents spinel-type product containing 18 to 90% iron oxides with balancing amounts of aluminum, magnesium, titanium, and silicon oxides. Prior to be used, catalyst is subjected to hydrodynamic and granulometric classification.

EFFECT: reduced total expenses due to use of substantially inexpensive catalyst capable of being repetitively used after regeneration, which does not deteriorate properties of original product.

2 cl, 6 ex

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