Ultrafast Oxidative Desulfurization of Diesel Fuel Catalyzed by Polyoxometalate-Based Catalyst Immobilized on Functionalized Y-Sba-15

Abstract

Y-SBA-15 was synthesied by doping Yttrium (Y) into SBA-15 using a solvent-free solid-state grinding method, and 1-butyl-3-methylimidazolium phosphomolybdic salt ([Bmim] 3 PMo 12 O 40 , abbreviated to [Bmim]PMoO ) was synthesized, and then it was loaded on Y-SBA-15. [Bmim]PMoO/Y-SBA-15 is a catalyst used for oxidative desulfurization (ODS). The physicochemical characteristics of the catalyst have been investaged by FT-IR, XRD, BET, FESEM, TEM, XPS, Contact angle testing, and EPR etc. The 25[Bmim]PMoO/10Y-SBA-15 showed highly catalytic activity in dibenzothiophene (DBT) ODS, and removing the complete sulfur compounds within 40 min under the conditions: V Oil = 10 mL, m catalyst =0.1 g, m [Bmim]PMoO : m [Bmim]PMoO/10Y-SBA-15 =25%, O/S = 4 (molar ratio). In addition, the concentration of aromatics had little effect on the DBT ODS. Sulfur compounds in real diesel might be reduced from 203 µg/g to 8 µg/g. The ODS reaction mechanism is also investigated. Hydroxyl radical •OH and superoxide radical •O 2− play crucial roles during ODS reaction.

Keywords: Oxidative desulfurization, Y-SBA-15, Keggin-type polyoxometalate, Dibenzothiophene