Study on the Synthesis of Clay-Based Titanium Silicalite-1 Catalytic Composite

A clay-based titanium silicalite-1 (TS-1) catalytic composite was synthesized using hydrothermal treatment to crystallize TS-1 (300-400 nm) on abentonite support. The presence of bentonite is favorable to supported growth attributed to the adsorption properties of the substrate which enhanced the interaction with the dissolved crystallizing species. The rapid crystallization on the bentonite support caused formation of silicalite-1 prior to Ti incorporation. An FT-IR spectroscopic study revealed that the Si defective sites were the exact location at which Ti was bonded. The Ti has been confirmed to exist in the form of a Si-O-Ti bridge instead of a Ti=O group in the clay-based TS-1. The influence of the synthesis temperature, duration, H 2O to SiO 2 molar ratio, and Ti and TPAOH concentrations in the starting gel on the characteristics of the clay-based TS-1 composite were also studied. In addition to the high and stable catalytic activity, the excellent settling efficiency of the clay-based TS-1 composite allowed it to become a reusable catalyst for TS-1-catalyzed processes.