Deep Oxidative Desulfurization of Dibenzothiophene in Simulated Diesel with Tungstate and H₂O₂ in Ionic Liquids

Abstract

A green extraction and catalytic oxidative desulfurization (ECODS) system composed of simple tungsten-containing catalyst, 30 wt% H₂O₂, and ionic liquids was discovered suitable for the deep removal of dibenzothiophene (DBT) in simulated diesel. In the case of the system comprising Na₂WO₄ · 2H₂O, 30 wt% H₂O₂ and 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim]BF₄), the removal of DBT could reach 99.7% at 60°C for 3 hr, which was superior to mere solvent extraction with ionic liquid or catalytic oxidation without ionic liquid. This desulfurization system could be recycled five times with a small decrease in activity.

Keywords:

• catalytic oxidation
• desulfurization
• extraction
• hydrogen peroxide
• ionic liquids

Notes

^a The biphasic mixture was stirred at room temperature for 15 min.

^b V(H₂O) = 1 mL.