Direct synthesis of mesoporous (C19H42N)4H3(PW11O39)/SiO2 and its catalytic performance in oxidative desulfurization

A novel mesoporous material (C19H42N)4H3(PW11O39)/SiO2 with different (C19H42N)4H3(PW11O39) loadings (6.3–19.4 wt.%) was prepared by direct sol–gel method. The material was characterized by XRD, FT-IR, Raman scattering spectroscopy, 31P CP-MAS NMR spectroscopy, XPS, XRF, N2 adsorption/desorption, DSC and HRTEM. The characterization results reveal that (C19H42N)4H3(PW11O39) was highly dispersed into silica matrix and its structure remained intact after formation of the material. The material possessed high surface area (543–1009 m2/g), pore volume (0.40–1.19 cm3/g), and pore walls thickness (5.85–9.37 nm) with interconnected worm-like mesostructure. Small angle XRD and N2 adsorption/desorption results show that the material retained its mesoporous structure for up to 14.9 wt.% (C19H42N)4H3(PW11O39) loading, further increase in percentage resulted in the formation of disordered structure with abundant micropores. The material was found to be highly active and reusable for oxidative desulfurization of bulky organosulfur compound DBT.