Synthesis of Ti-containing extra-large-pore zeolites of Ti-CIT-5 and Ti-SSZ-53 and their catalytic applications

Introduction of titanium into the frameworks of 14-ring extra-large-pore zeolites with CIT-5 (CFI-type, 7.2 × 7.5 Å) and SSZ-53 (SFH-type, 6.4 × 8.7 Å) topology has successfully been conducted by a chemical vapor deposition (CVD) method. The prepared titanosilicate zeolites have been characterized by XRD, SEM, UV–vis spectroscopy, IR spectroscopy, N2 adsorption, and elemental analysis. According to the characterization data, titanium is mostly incorporated into the framework of the zeolite in a tetrahedrally coordinated state. The catalytic epoxidation of cycloalkenes with H2O2 and tert-butyl hydroperoxide (TBHP) has been measured. The prepared titanosilicates with extra-large pores show superior performances for bulky molecule oxidation using TBHP as an oxidant compared to medium-pore TS-1 and large-pore Ti-beta.