Heterogeneous Catalysts Containing an Anderson-Type Polyoxometalate for the Aerobic Oxidation of Sulfur-Containing Compounds
E. A. Eseva, Maksim O. Lukashov, Kirill A. Cherednichenko, И. С. Левин, A. V. Akopyan
Abstract
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 °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.