Synthesis of hierarchically porous TS-1 zeolite with excellent deep desulfurization performance under mild conditions

Hierarchically porous TS-1 (HTS-1) zeolite with nanocrystal aggregate structure has been successfully synthesized by hydrothermal and steam-assisted crystallization (SAC) method with the aid of polyvinyl alcohol (PVA). It has been found that the formation of mesoporous aggregates was attributed to the construction of PVA three-dimensional network. The mesoporous aggregate structure could be well maintained by SAC method, resulting in HTS-1 with either surface titanium enrichment or highly interconnected mesopores and high external surface. Both could contribute to the excellent catalytic performance of HTS-1 in oxidative desulfurization of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT). The TOF numbers of HTS-1 reached a very high value to 114.9 h(-1) and 53.2 h(-1) in the oxidation of DBT and 4,6-DMDBT, respectively. Moreover, the HTS-1 showed good stability and remained similar to 90% of its initial activity even after 3 times cycle. The high catalytic activity and good stability suggest that HTS-1 is a promising catalyst for deep oxidative desulfurization.