Highly Efficient Extraction and Oxidative Desulfurization System Using Na7H2LaW10O36⋅32 H2O in [bmim]BF4 at Room Temperature

Highly efficient, deep desulfurization of model oil containing dibenzothiophene (DBT), benzothiophene (BT), or 4,6‐dimethyldibenzothiophene (4,6‐DMDBT) has been achieved under mild conditions by using an extraction and catalytic oxidative desulfurization system (ECODS) in which a lanthanide‐containing polyoxometalate Na₇H₂LnW₁₀O₃₆ ? 32 H₂O (LnW₁₀; Ln=Eu, La) acts as catalyst, bmim]BF₄ (bmim=1‐butyl‐3‐methylimidazolium) as extractant, and H₂O₂ as oxidant. Sulfur removal follows the order DBT>4,6‐DMDBT>BT at 30 ° C. DBT can be completely oxidized to the corresponding sulfone in 25 min under mild conditions, and the LaW₁₀/bmim]BF₄ system could be recycled for ten times with only slight decrease in activity. Thus, LaW₁₀ in bmim]BF₄ is one of the most efficient systems for desulfurization using ionic liquids as extractant reported so far.