Adsorption-enhanced oxidative desulfurization by a task-specific pyridinium-based porous ionic polymer

An adsorption-enhanced catalytic reaction approach was proposed to improve the kinetics of the oxidative desulfurization in which a task-specific porous ionic polymer (PIP) was designed to act as both of organosulfur adsorbent and catalyst support. Through a simple one-pot crosslinking of simultaneous quaternization and Friedel-Crafts alkylation reactions, the hierarchical pyridinium-based PIP of [PPYX]Cl was fabricated, which exhibited an outstanding adsorption capacity of dibenzothiophene (DBT) of 35.1 mgS g−1. When it was used as the support, its large surface area and positive charged network assured highly dispersion of (phosphotungstic acid) HPW species, resulting in HPW/[PPYX] hybrid catalysts. Among them, HPW/[PPYX]-0.5 outperformed that only within 45 min, a complete conversion of 100 mgS L−1 DBT model oil was accomplished under the optimized ODS conditions. Moreover, it also showed an excellent recycling stability that almost no loss of the catalytic reactivity after ten cycles due to the good affinity between HPW and [PPYX]Cl. Therefore, through this successful case of adsorption-enhanced oxidative desulfurization, PIPs could be promising supports for producing highly efficient heterogeneous catalysts.