Modified Y molecular sieve and preparation method and use thereof, supported catalyst, and hydrocracking method

摘要

The present invention discloses a modified Y molecular sieve, a preparation method and a use of the modified Y molecular sieve, a supported catalyst, and a hydrocracking method. The silica-alumina mole ratio in the surface layer of the modified Y molecular sieve is 20~100:1, and the silica-alumina mole ratio in the body phase of the modified Y molecular sieve is 8~30:1. When a hydrocracking catalyst prepared from the modified Y molecular sieve is used for hydrocracking, the hydrocracking catalyst is said to have a higher reactivity and higher nitrogen tolerance. The method for producing the sieve includes treating a Na-Y zeolite by ammonium exchange such that the Na content is not higher than 3 wt%; treating the sieve by primary dealumination so that the silica-alumina mole ratio in the sieve is increased by 2-8; treating the sieve with carbon deposition so that 60-90% of the pore volume is filled; treating the sieve with secondary dealumination to form a surface layer of the sieve in which the silica-alumina mole ratio is 10-80 compared with the silica-alumina mole ratio in the sieve treated by primary dealumination.