Patent ID: 11975980

Abstract:
A molecular sieve of MFI structure has a ratio of n(SiO2)/n(Al2O3) of more than 15 and less than 70. It has a content of phosphorus of 1-15 wt %, calculated as P2O5 and based on the dry weight of the molecular sieve and a content of the supported metal in the molecular sieve 1-10 wt % based on the oxide of the supported metal and the dry weight of the molecular sieve. The supported metal is one or two selected from lanthanum and cerium. The volume of mesopores in the molecular sieve represents 40-70% by volume of the total pore volume of the molecular sieve by volume, measured by a nitrogen adsorption BET specific surface area method, and the volume of mesopores means the pore volume of the pores having a diameter of more than 2 nm and less than 100 nm.