Method of preparing catalyst for median-temperature carbon monoxide-water steam conversion
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
The technical field
The invention relates to a method for preparing catalysts for medium-temperature conversion of carbon monoxide, which can be used in industry for preparation of nitric mixture for the synthesis of ammonia.
The level of technology
There is a method of preparation of the catalyst for conversion of carbon monoxide by precipitation of iron hydroxide from a solution of iron nitrate urea precipitator, which use ammonia water, followed by receiving iron-containing component, representing a suspension of iron hydroxide in the solution of ammonium nitrate. Simultaneously prepare the bichromate of copper dissolution basic carbonate of copper chromic acid, then mixed suspension of iron hydroxide with bichromate of copper and powdered promoters - Al(Oh)3and MgCO3Mg(OH)2, catalyst mass is dried, calcined, form [Technology catalysts / edited Ipomaea. L.: Chemistry, 1997, c.133].
The disadvantages of this method include low activity of the obtained catalyst, and the formation of large quantities of nitrogen oxides by heat treatment of the catalyst, leading to environmental pollution.
There is a method of preparation of the catalyst for conversion of carbon monoxide, comprising smeshivanie iron oxide powder with a solution of chromic acid, extrusion molding the obtained paste into granules, exposure to air, drying and calcination. By this method the mixture of iron oxide powder with a chromic acid is carried out in two stages: first, 20-50 % of iron oxide is pulverized in the presence of chromic acid to achieve the degree of dissolution of iron oxide 5,0-11,0 %, and then, the resulting fine suspension is mixed with the rest of the amount of iron oxide powder to form a paste humidity is 26.0-29.0 percent [As. Su 1235523 AI, B 01 J 37/04, 23/86, publ. BI No. 21, 1986].
A significant disadvantage of this method is used as a precipitant solution of ammonium carbonate, which complicates the technological process, cause undesirable foaming at the stage of receipt of carbonate of iron. The resulting catalyst contains up to 0.3 % sulfur compounds, which during operation causes the deactivation of the low-temperature copper-based catalyst for CO conversion.
Closest to the proposed to the technical essence and the achieved result, i.e. the prototype, is a method for preparing a catalyst for medium-temperature conversion of carbon monoxide with water vapor, including deposition of iron hydroxide from a solution of iron nitrate urea precipitator then receiving iron-containing component, the preparation of the bichromate of copper, mixing with the iron-containing component, drying, calcination, forming the catalyst mass. This method is characterized by the fact that as a precipitator use of ammonium-carbonate solution, the precipitate of iron hydroxide is separated and washed, dried, calcined at a temperature of 380-420°received iron-containing component, representing the iron oxide, mixed with bichromate of copper, the catalyst mass is humidified by water, mold, provalivajut in air, dried and calcined at a gradual rise of temperature with a speed of 30-50° [Patent RU, 2157731, B 01 J 37/04, publ. BI No. 7, 2000].
The disadvantages of the prototype should include the complexity and duration of the technological process of preparation, is not sufficiently high mechanical strength and activity of the obtained catalyst, the use of scarce and toxic chromium compounds. In the process of preparation of the catalyst rather laborious, time-consuming and energy-intensive are the stage of the preparation of a solution of chromic acid, chromate, copper, drying and calcination of the hydroxide of iron, which the proposed technical solution, are excluded. In addition introduces the operation of mechanical activation of iron hydroxide in the presence of oxides of copper and calcium.
Object of the invention is the creation of the joint venture is soba obtain catalyst for medium-temperature conversion of carbon monoxide with water vapor with high activity and mechanical strength while reducing and removing technological operations and eliminating toxic ingredients.
The problem is solved in the proposed method of preparation of the catalyst for medium-temperature conversion of carbon monoxide with water vapor, including deposition of iron hydroxide urea precipitator, leaching of iron hydroxide water from nitrate ions, a mixture with a compound of copper, molding, drying and calcination of the pellets, and the iron hydroxide is mixed with copper oxide and calcium at a molar ratio of Fe2O3:SiO:Cao=1:0,03-0,2:1,0-2,0, and then subjected to mechanical activation.
Information confirming the possibility of carrying out the invention
For the preparation of the catalyst according to the proposed method using iron hydroxide Fe2O3mo2Oh, obtained by precipitation from a solution of iron nitrate concentration of 380 g/l at a temperature of 60°C, pH 7.8 and constant stirring with 25 % aqueous ammonia solution. In the result of the interaction of a precipitate of Fe2About3mo2On the solution of ammonium nitrate. The precipitate was separated from the mother liquor, washed thoroughly with hot water to a residual content of nitrate-ions of less than 0.5% and remove excess moisture. For the preparation of 102 g of the catalyst take 95 g of iron hydroxide containing 64 g of iron oxide and 31 g of moisture, 4 g of calcium oxide, 2 g of copper oxide (molar ratio of Fe2 O3:CaO:SIO=1:1,5:0,125)that load in the drum vibratory mill VM-4. Then the resulting mass is introduced 25 g of water. The mass is thoroughly stirred for 30 minutes and formed into granules, which are dried at 100°C for 6 hours and then calcined at 45°C for 6 hours. The composition of the catalyst: Fe2O362,7 Million Tons %; CaO-33,3 %; CuO-4,0 %.
The catalyst is prepared analogously to example 1 with the only difference that for the preparation of 104 g of the catalyst charge and 84.6 g of iron hydroxide containing 57 g of iron oxide and 27.6 g of water, 41 g of calcium oxide and 6 g of copper oxide (molar ratio of Fe2O3:CaO:SIO=1:2:0,2), mass activate in a centrifugal planetary mill for 12 minutes. The composition of the catalyst: Fe2About3-54,8%; CaO-39,4 %; CuO-5,8 %.
The catalyst is prepared analogously to example 1 with the only difference that for the preparation of 99 g of the catalyst take 106,9 g of iron hydroxide containing 72 g of iron oxide and is 34.9 g of water, 26 g of calcium oxide and 1 g of copper oxide (molar ratio of Fe2O3:CaO:SIO=1:1:0,03), weight activated in a planetary mill AGO-2 for 5 minutes. The composition of the catalyst: Fe2About3-72,7%; CaO-25,3%; CuO-1,0%.
The mechanical strength of the granules of the catalyst was measured by the method of crushing the butt on the hydraulic hand pump.
The activity of the catalyst samples is assessed and on the degree of conversion of CO in the reaction of conversion of carbon monoxide with water vapor. Test conditions: temperature 350°s, steam:gas ratio=0,6. Space velocity of 5000 h-1. The content input =12,0 % vol.
The test results of physico-chemical properties of the catalysts are presented in the table.
|Example # PP||Mechanical strength at crushing the edge, MPa||Activity (degree maturing at t=350 °C|
|Example 1||11,0||of 89.1|
The table shows that the use of the claimed invention increases the mechanical strength of 1.8-2.0 times, and activity 11.0-15.4 per cent.
The preparation method of catalyst for medium-temperature conversion of carbon monoxide with water vapor, including deposition of iron hydroxide from a solution of iron nitrate urea precipitator, leaching of iron hydroxide water from nitrate ions, a mixture with a compound of copper, molding, drying and calcination of the pellets, characterized in that the iron hydroxide is mixed with copper oxide and calcium at a molar ratio of Fe2O3:SiO:Cao=1:0,03÷0,2:1,0÷2,0 and then subjected to mechanical is some activation.
FIELD: polymerization catalysts.
SUBSTANCE: invention disclose a method for preparing catalyst based on DMC (4,4'-dichloro-α-methylbenzhydrol) appropriate to be used in polymerization of alkylene oxides into polyol-polyethers comprising following stages: (i) combining aqueous solution of metal salt with metal cyanide aqueous solution and allowing these solutions to interact, while at least one part of this reaction proceeds in presence of organic complexing agent to form dispersion of solid DMC-based complex in aqueous medium; (ii) combining dispersion obtained in stage (i) with essentially water-insoluble liquid capable of extracting solid DMC-based complex and thereby forming biphasic system consisting of first aqueous layer and a layer containing DMC-based complex and liquid added; (iii) removing first aqueous layer; and (iv) removing DMC-based complex from layer containing DMC-based catalyst.
EFFECT: lack of negative effect on DMC-based catalyst activity.
16 cl, 1 tbl, 3 ex
FIELD: catalytic chemistry.
SUBSTANCE: the invention is dealt with the fields of catalytic chemistry. The invention offers a predecessor of the cobaltic catalyst, which contains a catalyst carrier impregnated with cobalt. All the restorable cobalt is present in the carrying agent in the form of a sustained cobalt oxide in accordance with a block formula CoOaHb, in which a ≥ 1.7 and b ≥ 0. The invention also offers alternatives of the method of preparation of the predecessor of the cobaltic catalyst. The technical result is production of a cobaltic catalyst with a higher activity.
EFFECT: the invention ensures production of a cobaltic catalyst with a higher activity.
20 cl, 10 ex, 12 tbl, 10 dwg
FIELD: chemical industry; production of catalytic compounds for polymerization of monomers.
SUBSTANCE: the invention is dealt with the field of polymerization of the monomers and with the methods of production of catalytic compounds and compounds, which are applied at polymerization of at least one monomer. The offered methods contain: 1) a treated solid oxide compound produced due to a contact at least of one solid oxide with at least of one compound having an electron-seeking anion; 2)a metallocenes compound of a metal from IVA group; 3) an organoaluminum compound. The technical result: production of a heterogeneous catalytic compound ensuring production of practically uniform particles of a polymer.
EFFECT: the invention allows to produce a heterogeneous catalytic compound ensuring production of practically uniform particles of a polymer.
71 cl, 99 ex, 13 tbl
FIELD: polymer production and polymer production catalysts.
SUBSTANCE: invention relates to synthesis of catalysts for production of cis-polybutadiene and butadiene/isoprene cis-copolymer, which can be employed in synthetic rubber industry. Task of invention resides in providing a novel method for synthesis of high-activity catalytic component, in particular neodymium neodecanoate, by reaction of neodymium oxide with neodecanoic acid in presence of metal chloride catalysts characterized by low acidity enabling conduction of process in stainless steal apparatuses and so making it possible to exactly controlling molar ratio of neodymium neodecanoate to free neodecanoic acid and water. Catalytic complex is formed by mixing neodymium neodecanoate-based catalytic component with butadiene, triisobutylaluninum, and diisobutylaluninum hydride in hydrocarbon solvent. Polymerization of butadiene or copolymerization of butadiene with isoprene is carried out in presence of thus formed catalytic complex in hydrocarbon solvent.
EFFECT: increased percentage of cis-1,4 units in polybutadiene or butadiene/isoprene copolymer and narrowed polymer or copolymer molecular weight distribution.
11 cl, 1 tbl, 45 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: polymerization catalysts.
SUBSTANCE: catalyst is prepared by mixing hydrocarbon solutions of titanium tetrachloride, triisobutylaluminum-diphenyl oxide complex, and 1,3-pentadiene at Al/Ti molar ratio from 0.9:1 to 1.2:1 and at temperature form -70 to +20°C, after which mixture of paraffin, aromatic, and naphthene hydrocarbons is added, in particular industrial or transformer oil in amount 0.05 to 2% on the weight of catalyst suspension.
EFFECT: increased catalytic activity and reduced dosage of catalyst in polymerization process, which allows production of rubber with reduced titanium compound level without increasing intensity of washing away titanium compounds.
2 cl, 1 tbl, 11 ex
FIELD: organic synthesis catalysts.
SUBSTANCE: catalyst is prepared from allyl chloride production wastes comprising 30-50% 1,3-dichloropropenes, 30-60% 1,2-dichloropropane, and 3-5% 1,2,3-trichloropropane, which are treated at 5-10°C with 30-50% dimethylamine aqueous solution in such amount as to ensure stoichiometric ratio of dimethylamine with respect to 1,3-dichloropropenes. Resulting mixture is held at 20-25°C for 0.5-1.0 h and then 40-44 sodium hydroxide solution is added in stoichiometric amount regarding dimethylamine, after which clarified waste is added to dimethylamine at 60-70°C and stirring in amount ensuring stoichiometric ratio of dimethylamine to 1,3-dichloropropenes contained in clarified waste. Mixture is aged for 2-3 h, organic phase is separated, and remaining interaction phase is supplemented by C1-C4-alcohol or benzyl alcohol at alcohol-to-dimethylamine molar ratio 1:(1-3).
EFFECT: reduced expenses on starting materials.
2 cl, 3 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: polymerization catalysts.
SUBSTANCE: invention, in particular, relates to synthetic rubber production and can be use in petrochemical industry. Invention proposes reaction of neodymium oxide or salt with C8-C20-carboxylic acid at acid-to-neodymium molar ratio between 2.2:1 and 5.0:1 in solvent and in presence of halogen-containing acid and/or Lewis acid at continuous stirring. Reaction proceeds directly upon dispersing and continuous renewal of reaction surface, milling surface ranging from 0.055 to 5.0 m2 per 1 L reaction mixture volume. Above-mentioned dispersing and continuous renewal of reaction surface are performed both consecutively and simultaneously for 1.0-3.0 h and, if necessary, reaction mixture is recycled. When consecutively carrying out both processes, dispersing is effected until conversion 75-85% is attained, after which reaction of neodymium oxide or salt is completed at continuous renewal of reaction surface during 0.5-1.0 h.
EFFECT: increased conversion of neodymium oxide or salt to 100% and reduced losses of raw materials and power.
8 cl, 1 dwg, 11 ex
FIELD: petroleum processing catalysts.
SUBSTANCE: invention related to hydrofining of hydrocarbon mixtures with boiling range 35 to 250оС and containing no sulfur impurities provides catalytic composition containing β-zeolite, group VIII metal, group VI metal, and possibly one or more oxides as carrier. Catalyst is prepared either by impregnation of β-zeolite, simultaneously or consecutively, with groups VIII and VI metal salt solutions, or by mixing, or by using sol-gel technology.
EFFECT: increased isomerization activity of catalytic system at high degree of hydrocarbon conversion performed in a single stage.
40 cl, 2 tbl, 19 ex
FIELD: chemical industry.
SUBSTANCE: the invention is pertinent to the field of chemical industry, in particular to production of a catalysts and processes of oxidation of ammonia in production of a weak nitric acid. The invention offers an ammonia conversion catalyst on the basis of the mixture of oxides of unitized structure and a method oxidation of ammonia in production of weak nitric acid. The catalyst represents a mixture of oxides of the over-all formula (AxByO3Z)k (MmOn)f, (NwPgvOv)r where: A - cation of Ca, Sr, Ba, Mg, Be, Ln or their mixtures; B - cations of Mn, Fe, Ni, Co, Cr, Cu, V, A1 or their mixtures; x=0-2, y=1-2, z=0.8-l.7; M - A1, Si, Zr, Cr, Ln, Mn, Fe, Co, Cu, V, Ca, Sr, Ba, Mg, Be or their mixtures; m=l-3, n=l-2; N - Ti, Al, Si, Zr, Ca, Mg, Ln, W, Mo or their mixtures, P - phosphorus, O - oxygen; w=0-2, g=0-2, v=l-3; k, f and r - mass %, at a ratio (k+f)/r=0-l, f/r=0-l, k/f = 0-100. The catalyst is intended for use in a composition of a two-stage catalytic system generated by different methods, also in a set with the trapping platinoid screens and-or inert nozzles. The technical result ensures activity, selectivity and stability of the catalyst to thermocycles at its use in two-stage catalytic system with a decreased loading of platinoid screens.
EFFECT: the invention ensures high activity, selectivity and stability of the catalyst to thermocycles at its use in two-stage catalytic system with a decreased loading of platinoid screens.
8 cl, 1 tbl, 5 ex