Acid Properties of MCM-36 Molecular Sieve and its Catalytic Behavior in Benzene Alkylation with Propylene

Pillared layered MCM-36 zeolite was synthesized from pure MCM-22 precursor with polymeric silica as pillaring agent. Characterization results of acidic properties from FT-IR indicate a decrease in the amounts of Lewis acidic and Brønsted acidic. The catalytic behavior of pillared layered MCM-36 zeolite in benzene alkylation with propylene was studied. It was found that pillared MCM-36 zeolite shows stable catalytic activity in a 200h time-on-stream measurement under a relatively high propylene velocity space. The excellent selectivity to cumene over MCM-36 should be mainly due to the decrease in the amount of Brønsted acidity, while the improvement of the catalytic activity of MCM-36 can be mainly assigned to the presence of a larger amount of structurally accessible acid sites caused by the increment of mesoporous volume in this material.