The Influence of TPOACl on the Post-Synthesis of Hierarchical Zeolite Y and the Catalytic Cracking Application

A hierarchical zeolite Y was prepared through a facile SiCl4 dealumination plus alkaline treatment process with the addition of surfactant TPOACl. It was investigated in detail by XRD, BET, MASNMR, NH3-TPD and Py-IR. Compared with single alkaline treatment, the alkaline treatment in the presence of TPOACl could protect the microporosity of zeolite and led to hierarchical pore structures with increased mesoporosity and narrow distribution of mesopores. Accordingly, the mechanism for the desilication and the formation of mesopores in the presence of TPOACl was proposed based on the measurement results of NMR and Py-IR. The EFAl species could be assembled to poly-aluminum species in the presence of TPOACl and leads to low content of Lewis acid sites. The hierarchical zeolite Y with high ratio of B/L and high percent of mesopores possesses excellent catalytic performance in the conversion of 1,3,5-TIPB.