FCC process using binary molecular sieves having a core and shell of different structures and compositions

摘要

Disclosed is a novel binary sieve catalyst useful for olefin upgrading and fluid catalytic cracking which comprisesPPa crystalline zeolite metallosilicate core and a shell selected from an aluminum phosphate molecular sieve (AlPO.sub.4), a silicon-substituted aluminophosphate (SAPO), a metal aluminophosphate (MeAPO), and a crystalline metal aluminophosphate (MeAPSO) and is generally synthesized by a method comprising:PPadding a powdered form of crystalline zeolite metallosilicate into an aqueous slurry comprising phosphoric acid, alumina source, metal salt and an amine, mixing the slurry for 1 to 12 hours in a Teflon liner at room temperature, sealing said slurry in an autoclave and placing said slurry in an oven at 130. degree. C. to 240° C. for 12-168 hours to form said binary molecular sieve catalyst, washing and drying the product, calcining the product at 530 to 570° C. in nitrogen for 5-15 hours, calcining the product in air for 1 to 3 hours to burn off the template.