Abstract: TS-1 zeolite was synthesized by dry gel conversion technique with ethylenediamine (EDA) as alkali source and tetrapropylammonium bromide as template. On this base, the hierarchical TS-1 was prepared with sucrose as meso/macropore template. The obtained samples were characterized by powder X-ray diffraction, UV-Vis spectroscopy, and N₂ physical adsorption-desorption. The catalytic performance of the samples was evaluated using the oxidation of small molecular thiophene (Th) and bulky molecular benzothiophene (BT). With the decrease of the EDA/H₂O molar ratio at the bottom of autoclave, TS-1 samples presented the trend of increase for the crystallinity, Ti content in framework, and the catalytic activity in Th oxidation. When the ethylamine and n-butylamine were used as the alkali source, it was difficult for TS-1 to crystallize. Hierarchical TS-1 possessed mesopore/macropore and exhibited higher catalytic performance than TS-1 in Th oxidation. For the oxidation of BT, hierarchical TS-1 synthesized with sucrose/SiO₂ molar ratio of 0.35 presented the highest activity and the BT removal rate could reach almost 100%. However, the TS-1 had no catalytic activity in oxidation of BT.

Key words: dry gel conversion, TS-1 zeolite, hierarchical pore, thiophene, benzothiophene, catalytic oxidation