Synthesis of a hybrid Anderson-type polyoxometalate in deep eutectic solvents (DESs) for deep desulphurization of model diesel in ionic liquids (ILs)

•A hybrid Anderson-type (ChO)2K0.2Na2.6IMo6 catalysts was developed in DES.•The (ChO)2K0.2Na2.6IMo6 shows high activity in ionic liquids ECODS.•This system can be recycled 20 times with an unnoticeable decrease in activity.

A novel hybrid Anderson-type polyoxometalate, {[(CH3)3N(CH2)2OH]2}[H0.2K0.2Na2.6(H2O)6][IMo6O24] (Abbreviated as (ChO)2K0.2Na2.6IMo6) was synthesized in a deep eutectic solvent and characterized by XRD, FT-IR, thermal analysis, electrochemical measurements and inductively-coupled plasma, atomic emission spectrometer (ICP-AES). This hybrid polyoxometalate was used as a catalyst in ionic liquids (ILs) for desulfurization of model diesel. The catalyst (ChO)2K0.2Na2.6IMo6 in the extraction and catalytic oxidative desulfurization (ECODS) system, containing H2O2 and 1-octyl-3-methylimidazolium tetrafluoroborate (OmimBF4), displayed so high activity that the removal of DBT can reach 100% at 60 °C in 60 min. Sulfur removal for S-compounds was in the following order: DBT > 4,6-DMDBT > BT. The desulfurization system shows so good stability that it can be recycled 20 times without noticeable decrease in activity.