Industrial & Engineering Chemistry Research, Vol.59, No.31, 13932-13939, 2020
Fine-Tuned Hierarchical Architecture of MWW Zeolites for Highly Efficient Alkylation via Suitable Accommodation
The hierarchical structure of zeolites plays a crucial role in determining their catalytic performance. Here, the effect of the hierarchical architecture and surface topology of pillared MWW zeolites on the catalytic properties of liquid alkylation between mesitylene and benzyl alcohol was investigated. Pillared MWW zeolite catalysts exhibited excellent activity (similar to 100% conversion) due to their elegant pore architecture, which could largely improve the accessibility of bulk molecules toward active sites on the external surface. In addition, molecular simulation showed that lamellar MWW zeolites with a 12-membered ring semicup surface topology could more effectively accommodate and stabilize the large intermediates formed in alkylation reactions compared with MFI zeolites, resulting in outstanding selectivity for 2-benzyl-1,3,5-trimethylbenzene (similar to 100%). The Thiele modulus (phi) and effectiveness factor (eta) verified that the resultant pillared MWW zeolites possessed a high degree of utilization without internal diffusion constraints under the present reaction conditions.