Synthesis of hierarchical TS-1 zeolite via a novel three-step crystallization method and its excellent catalytic performance in oxidative desulfurization

Hierarchical TS-1 (HTS-1) zeolite has been successfully synthesized through a novel three-step crystallization method by using a cheap and eco-friendly polymer PVA as the mesopore template. The HTS-1 particles possess an interesting stacking structure and are constructed of smaller crystals with an average diameter of 30   nm. The mesopores of HTS-1 are formed by the stacking of the smaller TS-1 nanocrystals . The catalytic results show that the HTS-1 exhibits much higher catalytic activity than conventional TS-1 in the oxidative desulfurization of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) due to the presence of intracrystal mesopores. In addition, the three-step crystallization method plays a key role in the preparation of HTS-1, which effectively solves the problem that PVA is unstable and unsuitable to be used as mesopore template under high crystallization temperature .