FIELD: oil and gas industry.
SUBSTANCE: catalytic cracking catalyst and its preparation are disclosed. The catalyst contains from 20% to 40% by weight, per dry substance, of Y-type molecular sieve modified by rare earth elements, from 2% to 20% by weight, per dry substance, of aluminum oxide containing an additive and from 30% to 50% by weight, per dry substance, of clay; wherein aluminum oxide containing the additive contains, per dry substance and per the mass of aluminum oxide containing the additive, from 60% to 95% by weight of aluminum oxide and from 5% to 40% by weight of the additive, which is one or more compounds selected from a group that consists of compounds containing alkaline earth metal and/or phosphorus. The Y-type molecular sieve modified with rare earth elements has a content of rare earth element oxides ranging from 4% to 12% by weight, a phosphorus content ranging from 0% to 10% by weight per P2O5, a sodium oxide content of no more than 1.0% by weight, the total pore volume ranging from 0.36 ml/g to 0.48 ml/g, a percentage of the pore volume of secondary pores having a pore size from 2 to 100 nm, and the total pore volume of the Y-type modified molecular sieve ranging from 20% to 40%, the constant of a crystal lattice ranging from 2.440 to 2.455 nm, the percentage of the content of non-framed aluminum and the total content of aluminum, which makes up the Y-type modified molecular sieve, which is no more than 10%, the fracture temperature of the crystal lattice, which is not less than 1060°C, and the ratio of acid B and acid L in the total acid content of the Y-type modified molecular sieve, which is not less than 3.5, when determined by infrared spectroscopy with pyridine adsorption at 200°C. The method for preparation of the catalytic cracking catalyst includes following stages: preparation of the Y-type molecular sieve modified with rare earth elements, formation of a suspension containing the Y-type molecular sieve modified with rare earth elements, aluminum oxide containing the additive, clay and water, and spray drying, wherein aluminum oxide containing the additive contains, per the weight of aluminum oxide containing the additive, from 60% to 95% by weight of aluminum oxide and from 5% to 40% by weight of the additive, which is one or more compounds, selected from the group that consists of compounds containing alkaline earth metal and/or phosphorus.
EFFECT: when used for catalytic cracking of heavy oils, the catalyst exhibits increased activity of heavy oil conversion, less selectivity for coke and increased gasoline yield, liquefied gas yield, light oil yield and full liquid yield.
20 cl, 1 dwg, 10 tbl, 12 ex
