Metal Oxide Supported Vanadium Substituted Keggin Type Polyoxometalates as Catalyst For Oxidation of Dibenzothiophene

Supported polyoxometalatate H₄[γ-H₂SiV₂W₁₀O₄₀]·nH₂O with metal oxide i.e. silica, titanium, and tantalum was successfully synthesized via wet impregnation method to form H₄[γ-H₂SiV₂W₁₀O₄₀]·nH₂O-Si, H₄[γ-H₂SiV₂W₁₀O₄₀]·nH₂O-Ti, and H₄[γ-H₂SiV₂W₁₀O₄₀]·nH₂O-Ta. Characterization was performed using FTIR spectroscopy, X-Ray analyses, and morphology analyses using SEM. All compounds were used as the catalyst for desulfurization of dibenzothiophene (DBT). Silica and titanium supported polyoxometalate H₄[γ-H₂SiV₂W₁₀O₄₀]·nH₂O better than tantalum due to retaining crystallinity after impregnation process. On the other hand, compound H H₄[γ-H₂SiV₂W₁₀O₄₀]·nH₂O-Ta showed high catalytic activity than other supported metal oxides for desulfurization of DBT. Optimization desulfurization process resulted in 99% conversion of DBT under a mild condition at 70 °C, 0.1 g catalyst, and reaction for 3 hours. Regeneration studies showed catalyst H₄[γ-H₂SiV₂W₁₀O₄₀]·nH₂O-Ti was remaining catalytic activity for desulfurization of DBT. (paper)