One-pot oxidative-adsorptive desulfurization of model and real fuel using micro-mesoporous SiO2 aerogel supported MoO3

Abstract

In this research, micro-mesoporous SiO2 aerogel was used as support with different percentages of MoO3 and evaluated simultaneously as a catalyst for oxidation of dibenzothiophene (DBT) and as an adsorbent for oxidation products. Among studied weight percentages of MoO3, the SiO2 aerogel-supported catalyst with 1.5 wt% of MoO3 indicated the higher decline in C/C0 of DBT after 60 min (0.06). The characterization of the as-prepared catalysts by XRD, FESEM, EDX, FTIR, BET-BJH, and TEM indicated that MoO3 nanoparticles were uniformly dispersed on the surface of silica aerogel at all studied percentages. Despite a regular reduction in porosity with increasing MoO3 content, catalytic activity in DBT oxidation enhanced due to enhancing MoO3 content, amount of active sites, and hydrophilicity of surface for adsorbing H2O2, which is dissolved in water. Successive runs of oxidative-adsorptive desulfurization confirmed the stability of the MoO3–SiO2 aerogel catalyst. Examination of spent catalyst indicated that while crystalline structure remained unchanged, the porosity of spent catalyst decreased due to adsorption of DBT sulfones on the surface. In the following Iranian gasoil was subjected to the novel method of desulfurization and the GC-MS result indicated a noticeable reduction in sulfur-containing components of fuel after desulfurization.