Preparation and characterization of Beta/MCM-41composite zeolite with a stepwise-distributed pore structure

A Beta/MCM-41 composite zeolite with a stepwise-distributed pore structure was prepared with a silica-alumina source originated from alkaline treatment of zeolite Beta. The material was characterized by various techniques. The results indicated that this composite possesses a mesopore system of MCM-41 and the microporous structure of Beta zeolite. Hydrothermal stability and acidity was improved over MCM-41 due to the introduction of Beta building units into the mesopore walls. The composite was used as the support of a Pd-Pt catalyst for the hydrogenation of naphthalene in the presence and absence of 4, 6-dimethyldibenzothiophene. It was demonstrated that the catalyst has an enhanced activity and sulfur tolerance during naphthalene hydrogenation.

Graphical AbstractIn an attempt to design a family of sulfur-tolerant noble catalysts, a stepwise-distributed pore structure Beta/MCM-41 composite was prepared with a silica-alumina source originated from alkaline treatment of zeolite Beta. This approach takes the advantages of meso and micro-pore structures, shape selectivity and hydrogen spillover effects, and the diffusion barrier is minimized.Figure optionsDownload as PowerPoint slide