A gold catalyst stabilized in an open-porosity TS-1 zeolite for the direct epoxidation of propylene

Synthesis of hierarchical zeolites has been proven to be an effective strategy for improving reactant accessibility to active sites and extending catalyst lifetimes. Existing synthesis methods typically generate mesopores within zeolite crystallites instead of inside zeolites with an open-structure porosity. Here we have developed a general synthesis method by optimizing the crystallization conditions and molecular structures of the polymer template and linkage reagent, resulting in the formation of hierarchical MFI-, MEL-, BEA- and CHA-type zeolites with open porosity formed by highly interconnected microporous channels. Based on this method, we prepare a hierarchical TS-1 zeolite with open porosity as a support for a gold catalyst. The resultant Au/TS-1 catalyst exhibits high activity and stability for the direct epoxidation of propylene with H 2 and O 2 , which is associated with the intimate contact between the gold and titanium sites and the zeolite’s unique pore structure.