The method of obtaining long-chain hydrocarbons from co and h2in the liquid phase
Usage: petrochemistry. Essence: to obtain long-chain paraffin hydrocarbons from CO and H2in the liquid phase using finely dispersed, spherical catalyst containing 91-98 wt.% oxides of cobalt or iron and one or more socialization - oxides of molybdenum, zirconium, potassium, copper in an amount of 2 to 9 wt.%. The process is carried out at a temperature of 200-350oWith a molar ratio of H2/CO equal 1-3:1, the hydrogen pressure of 1-5 MPa. The catalyst obtained by co-deposition of salts of the base metal and one or more promoters with the introduction of an aqueous solution of 5-10 wt.% viscous organic phase. Technical result: the achievement of spherical catalyst particles in a viscous organic phase and increase the efficiency of the process. table 2., 1 Il. The invention relates to a method for producing long-chain paraffins C10-C25and chemical products from CO and H2.The progress of technology for synthetic liquid fuel according to the method of Fischer-Tropsch over the last decade has yielded significant results due to the solution of complex programs. The main directions of scientific research are to develop new catalytic the feature products of FT synthesis as raw materials for the chemical industry has long been known. The first experiences of carrying out synthesis in the liquid phase held in 1930 In 1939-1942, experiments with iron catalysts were continued by the company Ruhrchemie. During the war the company BASF and after the war the firm Bureau of Mines, Fuel Research Station was also developed ways of synthesis in the liquid phase. In 1955 in India was designed plant capacity of 250 thousand tons of hydrocarbons per year Koppers company.Advantages of fluidized bed of catalyst in the FT-technology explore actively the company "Badgerlo" and "Schell-MDS". The first reactor was tested in the late 70-ies . In 1990 he developed a reactor Slurry-bed" with a diameter of 1 m Modern reactor Slurry-bed"(1993) was developed by the company Sasol. A reactor having a height of 22 m and a diameter of 5 m, consists of a casing and cooling coils, in which is formed pairs. Synthesis gas barbthroat from the bottom and rises up through the layer of "slurry" phase, which consists of a heavy liquid reaction products. The catalyst particles distributed therein in suspension, may be a catalyst carryover. The reactor has a number of advantages. The conditions corresponding isothermal (due to mixing), and the process temperature may be higher than in the reactor with a fixed bed of catalyst . It is possible to achieve more than the go without difficulty, that allows you to replace the catalyst from time to time without downtime. In the reactor produced products heavier than under similar conditions in the reactor with fixed bed.As a liquid environment more suited fraction of hydrocarbons produced by the Fischer-Tropsch synthesis, with a sufficiently high boiling point.For FT-synthesis in the liquid phase, in principle, applicable to any catalysts, but to make a long-chain paraffins given recently preferred catalysts without media.As the base metal catalysts for FT synthesis using iron and cobalt, under the influence of various reagents on the freshly prepared catalysts of the iron group change in the composition and structure of the catalyst, there are really active phase in the FT-synthesis . Industrial process "Sasol", developed in the late 80-ies were conducted on iron catalyst at 220-340oC and hydrogen pressure, 24-25 ATM. The yield of hydrocarbons 75-95%, from about 60% olefins. Cobalt catalysts are used at normal pressure, a temperature of 200-300oWith or moderate 5-30 ATM and 180-250o.The first catalysts consisted of oxides; for example, only the oxide cob Modern cobalt catalysts consist of an oxide of the substrate (Si, Al, Ti, Zr, Mg, Si, Al, Ga, Ce, C, molecular sieves, zeolites). Promoters contribute to the restoration, because the catalyst is poisoned by the gradual oxidation or deposition of heavy hydrocarbons. Zr, V, Ti, Mg, Mn, Cr, Th, CE, La, Ni, Fe, Mo, W, Nd, elements of the Ia, IIA, and IB subgroups increase the activity and selectivity towards heavy hydrocarbons .A known method of producing hydrocarbons from synthesis gas on ruthenium catalyst (Ru/SiQi), as a carrier of ruthenium using silica gel. The degree of conversion of carbon to 9.3%, the selectivity for C3-C10the hydrocarbons of 62.3%. The disadvantages include low degree of conversion and selectivity for the target products.The known method of hydrocarbon synthesis catalyst comprising Co, oxides of Mg, Zr on the media - the diatomaceous earth in the following ratio of components: 100Co-6ZrO2-10MgO. In the synthesis at atmospheric pressure, at T=190-200oC, the yield of liquid hydrocarbons heavy wide faction - 130-190 g/nm3the content of solid paraffin 10%. In the synthesis under pressure of 1.0 MPa for the catalysts 100Co-6ZrO2or TiO2-10MgO-200 on kieselguhr, the main product is solid paraffin .The catalyst is known (A. C. the USSR 599832) containing, wt.%: Co - 28,0-31,4; Mo the population 7-20% zeolite the rest of it. The catalyst does not allow CFT process to earn a substantial amount of hydrocarbons having a boiling point in the range 225-335oC.As the prototype uses a process developed by firms BASF and Bureau of Mines. The process is carried out using a precipitated iron catalyst and synthesis gas of different composition. Process temperature 230-260oWith, a hydrogen pressure of 1 MPa provides the conversion of synthesis gas by 90%. The liquid product is 79% of hydrocarbons boiling within the gasoline (50-190o(C) and 13% within the diesel boiling fraction (220-320oC). Disadvantages: loss of catalyst in the form of dust, carried away by the oil; the clogging of the separator for slurry catalyst; a small amount (50%) of spherical particles of catalyst .The present invention is to develop a preparation of catalysts by co-deposition for selective receipt of the CO and H2hydrocarbons With10-C25.The solution of this problem is achieved by a catalyst comprising as a main metal cobalt or iron, the oxides of copper, potassium, zirconium, molybdenum is deposited by precipitating in water solution, which is injected 5-10% viscous organic phase.the main metal - With or Fe and socialization - salts of si, Zr, Mo, K. the salt Concentration of the base metal in a solution of 5-10%, the deposition is performed with urea to pH8-9 and bringing the pH to strongly alkaline with 25% ammonia solution. The synthesis is carried out at 60-80 ToC. the precipitate is filtered. Heat treatment of the catalyst is carried out at T= 95-120oC for 4 h in a muffle, the resulting mass is heated to 200oWith translation hydroxide into oxide. Recovery of the catalyst is carried out at T= 200-500oWith the flow of H2or (H2+CO), volumetric rate of supply of the reducing agent 9-12 l/hExample 1 as the primary metal salt took salt of iron and in addition the solution was introduced to 7.2 ml of 0.5 n KOH. Heated to 60oWith water successively under stirring input salts of Fe, Zr, Mo. Then enter 5-10% pre-heated viscous organic phase. Deposition conduct urea to pH 8-9 and then brought to pH 10-11 25% ammonia solution. Simultaneous coprecipitation of all salts in the viscous phase is achieved by the formation of fine sediment with particles of spherical shape. The resulting suspension was filtered and washed with water. Then the catalyst is subjected to heat treatment.The obtained rolled is the recovery of the catalyst in a stream of hydrogen with a volume flow rate of hydrogen 12 l/h, it is examined for activity in the process of the Fischer-Tropsch synthesis at a temperature of 200-350oWith a molar ratio of H2/CO equal to (1-3):1, the hydrogen pressure of 1 MPa.Schematic diagram of the reactor shown in the drawing.The composition of the products obtained: C1-C5to 10.2 wt.%, With6-C7of 20.4 wt.%, C8-C23- 69,4% by weight, of these gaseous - of 14.5 wt.%, liquid of 79.5 wt.%, hard to 6.0 wt.%.Process conditions and results are presented in table 1.Example 2 Preparation of catalyst carry out analogously to example 1. Example 2 used a different viscous organic phase is glycerin. The resulting catalyst contains, wt%: Fe2O3- 96 ZrO21 Moo3- 1 K2O - 2 the Composition of the products obtained in FT-synthesis: C1-C5- 10.0 wt.%, With6-C7- 20.0 wt.%, C8-C23- 70,0 wt.%, of them gas is 13.0 wt.%, liquid - 80,0 wt.%, solid - 7.0 wt.% The introduction of glycerol leads to a significant increase in the activity of the catalyst. Achieved greater than that of the prototype, the yield of liquid products and reduced gas output, however, glycerin is easily mixed with water and technology has been the synthesis of the catalyst in the paraffin-based cobalt.Data on the composition of the catalysts, activity and composition of the liquid hydrocarbons are presented in table. 1.P is for drinking, preparing, the recovery and study of the activity of the catalysts as in example 1. A special influence on the catalyst activity has Mo and Zr. Co-Zr catalyst operates at higher temperatures.Heat treatment, rehabilitation and research activity of the catalysts as in example 1. Data on the composition of the catalysts, activity and composition of the liquid hydrocarbons are presented in table. 2.According to REM all the catalyst samples are associates of spherical particles with d=0.1 to 0.05 mm in the organic phase (90%). Due to its density and sphericity decreased entrainment of the catalyst and the catalyst bed remains fixed. Variation catalysts affect the yield of liquid products, although the total activity of cobalt catalysts is higher than iron.Data analysis the table shows that the inventive method allows to obtain Uglevodorody10-C25from synthesis gas in the liquid phase using spherical, fine precipitated the proposed catalyst, since the contact time of synthesis gas with a catalyst to the conversion in the prototype is 16.2 (XCO=45% U=250 h-1L=6 m), while in the proposed method, the specified conversion to kabutomushi
1. B. Jager, M. E. Dry, T. Shingles, Steynberg, "Experience with a new type of reactor of Fischer-Tropschs Sinthesis", Catalyst Letters, 7 (1990) 293-302 C.2. M. F. Post, A. Van't Hoog, J. K. Minderhound and S. T. Sie, ALChEJ. 35(7), 1989, 225-274 C.3. Kagan, Y. B., Loktev, S. M., and others, the Development of ideas about the mechanism of synthesis from CO and H2on iron catalysts. Petrochemicals, 1988, 28 so.4. Catalysis in C1chemistry / Ed. by C. Border, Per. s angl. I. I. Moiseev. L.: Chemistry, 1987.5. B. Jager, R. Espinoza, Catalysis Today 23 (1995) 17-28.6. Nefedov B. K. Syntheses of organic compounds based on carbon monoxide. M.: Nauka, 1978, S. 8-10.7. Chemicals from coal / Ed. by Y. Falbe. M.: Chemistry, 1980, 640 S.
The method of obtaining long-chain paraffin hydrocarbons from CO and H2in the liquid phase in the presence of a catalyst, characterized in that the process uses fine, spherical catalyst obtained by coprecipitation of salts of the base metal is cobalt or iron in the number 91-98 wt. % and one or more socialization - salts of molybdenum, zirconium, potassium, copper in the number 2-9 wt. %, while for the above catalyst in aqueous solution is injected 5-10 wt. % the components of the viscous organic phase and the above process is carried out at temperature
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