Vanadia Nanoparticles Encapsulated in Mesoporous Silica As a Rattle-Like Structure for Oxidation of Dibenzothiophene: A Kinetic Study

A rattle-like structure of V2O5 encapsulated in mesoporous silica was successfully prepared through a surfactant supported selective etching strategy. The structural analysis showed that V2O5 nanoparticles in the core of mesoporous hollow silica spheres with void diameter similar to 290 nm, V2O5 core diameter similar to 93 nm, amorphous SiO2 shell thickness similar to 17 nm, surface area of similar to 368.19 m(2)/g and average pore radius of 16 nm. The as-prepared material was employed in catalytic oxidation of dibenzothiophene (DBT) in the presence of H2O2 as an oxidizing agent at different conditions of temperature, contact time and initial concentration using a batch system under either stirring or ultrasonication. The ultrasonication was found to be more effective (similar to 100%) and faster in oxidation process than the stirring (similar to 68%, after 5 h). The analysis of the outputs significantly indicated the adsorption of the produced sulfone onto the catalyst surface. The catalytic system exhibited high removal efficiency, qe (similar to 493 mg/g), as detected experimentally at ambient condition. The thermodynamic analysis confirms the spontaneous physic-sorption nature of the adsorption process with adsorption energy similar to 2.155 kJ/ mol. The intra-particle diffusion model indicates that the process passes through three stages to attain the equilibrium state.