Heterogeneous Catalysts Containing an Anderson-Type Polyoxometalate for the Aerobic Oxidation of Sulfur-Containing Compounds

New highly efficient heterogeneous catalysts based on an immobilized Anderson-type polyoxometalate supported on the functionalized SBA-15 surface have been successfully synthesized and characterized by FT-IR, XRD, N2 adsorption-desorption isotherms, BET, SEM, TEM, EDX, and XPS analyses. The catalytic activity was investigated in the aerobic oxidative desulfurization of a model fuel. Heterogeneous catalysts were synthesized by various methods of immobilization using organic fragments of different natures. An efficient method of immobilization based on the grafting of N-methylimidazole as a cation-forming agent has been shown. The effect of temperature, dosage, and active phase loading on the conversion of dibenzothiophene (DBT) was studied. The highest activity was shown by the CoMo-0.5IL-SBA catalyst (IL = 1-methyl-3-(trimethoxysilylpropyl)-imidazolium cation), in the presence of which 100% DBT removal is achieved within 90 min at 120 degrees C at a catalyst amount of 0.2 wt %. Moreover, the immobilized catalyst could be recycled 5 times without a significant loss of catalytic activity.

Automated summary

The study focused on the synthesis and characterization of new efficient heterogeneous catalysts based on various immobilization methods, with the most effective method being the use of N-methylimidazole as a cation-forming agent.