High-index planes T-Nb2O5 using self-assembly strategy for aerobic oxidative desulfurization in fuels

High-index planes viewed as reactive facets are possessed of the high-density, low-coordination atoms, which are distributed at catalytic sites with high activity, such as steps, edges and kink sites. Herein, the orthorhombic niobium pentoxide (T-Nb2O5) is synthesized, with the elevated ratio of high-index planes, first for aerobic oxidative desulfurization (ODS) of the refractory aromatic sulfides. Through a solvent evaporation-induced self-assembly strategy, mesoporous structure Nb2O5 with three different crystal phases, amorphous, pseudo -hexagonal and orthorhombic, are prepared using the calcination method. The proportion of high-index facets increases, as raising the calcination temperature, which contributes to the faster production of the superoxide free radical (center dot O-2(-)) intermediate using molecular oxygen as the green oxidant. Under optimal conditions, a 100% sulfur removal rate is obtained using 650 degrees C-T-Nb2O5 within 7 h, showing its excellent catalytic performance. The cycle experiments confirm the stability of the prepared 650 degrees C-T-Nb2O5 after 8 times regeneration process, showing a promising prospect of NbOx-based materials for ODS under mild conditions.

Automated summary

High-index planes in orthorhombic niobium pentoxide were synthesized for aerobic oxidative desulfurization, showing excellent catalytic performance at 650 degrees Celsius and stability after 8 regeneration cycles.