FIELD: chemistry.
SUBSTANCE: invention relates to oil-refining and petrochemical industry and production of catalysts used in conversion of C2-C12 aliphatic hydrocarbons and methanol to high-octane gasoline and aromatic hydrocarbons. Described is a zeolite-containing catalyst for converting C2-C12 aliphatic hydrocarbons and methanol to high-octane gasoline and aromatic hydrocarbons, which contains zeolite ZSM-5 with silica modulus SiO2/Al2O3=40-100 mol/mol and residual content of sodium oxide of 0.02-0.04 wt %, zeolite structural units and a binding component, wherein the zeolite structural units of the catalyst are niobium oxide and iron oxide or a mixture of oxides of said metals and zirconium oxide, and chromium oxide, with the following content of components (wt %): zeolite 65.00-85.00; ZrO2 0-3,00; Nb2O5 0-0.50; Fe2O3 0-1.00; Cr2O3 0-3.00; Na2O 0.02-0.04; binding component - the balance. Described is a method for obtaining a zeolite-containing catalyst, which involves mixing reactants, hydrothermal synthesis, washing, drying and calcining the residue. The reaction mixture obtained by mixing aqueous salt solutions of aluminium, zirconium, niobium, iron, chromium and sodium hydroxide, silica gel, zirconium sulphate, niobium pentachloride, inoculating zeolite crystals with a ZSM-5 structure in Na- or H-form, a structure-forming agent, for example diethylene triamine (bis-(2aminoethyl)amine) is fed into an autoclave, where hydrothermal synthesis is carried out at 160-190°C for 20-80 hours with constant stirring; at the end of hydrothermal synthesis, Na-form pulp of the zeolite is filtered; the obtained residue is washed with tap water and taken for salt ion exchange by treatment with aqueous ammonium chloride solution while heating and stirring the pulp; the pulp obtained from salt ion exchange is filtered, washed with tap water and then washed with dimineralised water to residual sodium oxide content of 0.02-0.04 wt % with respect to the dried and calcined product; the washed residue of the ammonium zeolite form is taken for preparation of the catalyst mass by mixing the ammonium zeolite form with active aluminium hydroxide; the obtained catalyst mass is extruded and granulated; the granules are dried at 100-110°C and calcined at 550-650°C; the calcined granules of the zeolite-containing catalyst are sorted; the fraction of the finished zeolite-containing catalyst is separated, and the fraction of granules smaller than 2.5 mm is ground into homogenous powder and returned to the step of preparing the catalyst mass. Described also is a method of converting C2-C12 aliphatic hydrocarbons and methanol to high-octane gasoline and aromatic hydrocarbons, which involves heating and passing material - vapour of straight-run gasoline fraction of oil or methanol through a fixed bed of the catalyst described above.
EFFECT: achieving high phase purity of the zeolite catalyst and wide distribution of acid sites thereof according to strength, introduction of more than one modifying element into the zeolite structure, high quality and output of end products on the disclosed catalyst.
4 cl, 9 tbl, 15 ex
Authors
Dates
2013-03-27—Published
2009-01-19—Filed