One step non-hydrodesulfurization of fuel oil: Catalyzed oxidation adsorption desulfurization over HPWA-SBA-15

Abstract

HPWA-SBA-15 has the typical structure of mesoporous molecular sieve SBA-15 and Keggin structure of H 3PW 12O 40 (HPWA). It was initially used in the catalyzed oxidation adsorption desulfurization of model fuel composed of dibenzothiophene (DBT) and isooctane, using tert-butyl hydroperoxide ( t-BuOOH) as oxidant. A series of catalysts including SBA-15 modified with different kinds of acid and several microporous materials containing HPWA were tested in the desulfurization of model fuel, it is shown that HPWA-SBA-15 has the best desulfurization capacity as catalyst and sorbent, it can remove DBT in nine tenths in one-step. Several comparison experiments were designed for the exploration of the function of HPWA-SBA-15 in the desulfurization. It is concluded that HPWA-SBA-15 has both catalytic oxidation ability and adsorption ability. The non-polar DBT can be converted into polar DBT sulfone that is easily absorbed on HPWA-SBA-15. FTIR characterization indicates the existence of intermediate of [O–O] structure in the desulfurization. Both the 31P NMR spectra of HPWA-SBA-15 before and after regeneration and the desulfurization results of these two samples indicate that HPWA-SBA-15 has good regenerating ability.