Ti-modified hierarchical mordenite as highly active catalyst for oxidative desulfurization of dibenzothiophene

Abstract

Ti-modified hierarchical mordenites (Ti/MM) were prepared using tetrabutyl orthotitanate (TBOT) as the precursor of Ti species by incipient wetness impregnation technique. The introduced Ti species were located outside the micropores in mordenite due to the large molecular size of TBOT. As a result, the active Ti species over hierarchical mordenites are easily accessible. The catalytic results indicated that Ti/MM were highly active ODS catalysts in the oxidative desulfurization (ODS) of dibenzothiophene due to rich mesoporosity. The sulfur removal content over a Ti-modified hierarchical mordenite (Ti/MM-0.5) with relatively large mesopore volume reached 98.6% after a reaction time of 120min at 333K by using H2O2 as oxidant, which is nearly four times as that over Ti-modified conventional mordenite. Accordingly, the sulfur content in model fuel was reduced from 1000ppmw to 14ppmw. These results indicated that Ti-modified hierarchical mordenite with rich accessible Ti sites and low cost has potential applications for ODS of transportation fuels.