Sn-Beta Zeolite Catalysts with High Sn Contents Prepared from Sn–Si Mixed Oxide Composites

The hydrothermal preparation of Sn-beta zeolites with high Sn contents is an eminent issue in zeolite syntheses, since these zeolites are some of the most anticipated materials for industrial catalysis. In this work, first, mechanochemical treatment was utilized to obtain a Sn–Si mixed oxide composite, in which the Sn was found to be homogeneously distributed inside the silica network. The composite was further used as the reactant for the crystallization of Sn-beta zeolite catalysts. Incorporation of Sn into the framework was achieved up to Sn/(Sn+Si)=1.6 mol %, which is the highest value reported by far using conventional hydrothermal treatment. A high catalytic performance for glucose isomerization was also confirmed. These results suggest that the utilization of a mixed oxide composite is a critical method for the preparation of stannosilicate zeolites with high Sn contents through hydrothermal treatment.