Surface Aerophilicity Engineering of Heterogeneous Catalysts for Enhanced Catalytic Ozonation

Abstract

Heterogeneous catalysts for catalytic ozonation are elaborately designed with commendable intrinsic activity, while their industrial applications are limited by inadequate mass transfer of ozone (O3). In this work, it is demonstrated that engineering the surface aerophilicity of heterogeneous catalyst enables fast mass transfer of O3 reactant, giving rise to much enhanced catalytic ozonation performance. Taking active 4A zeolite catalyst as an example, the aerophilicity of spherical 4A zeolite can be greatly enhanced by coating polytetrafluoroethylene (PTFE) with low surface energy, and the optimized sample exhibits a 99.5% removal of atrazine (ATZ) within 20 min (corresponding to a k of 0.269 min−1), much better than 4A zeolite without surface aerophilicity engineering (k≈0.156 min−1). The PTFE coating does not change the ozone activation mechanism and degradation pathways for ATZ, further demonstrating that the enhanced ozonation activity is attributed to the enhanced mass transfer process. In addition, the general applicability of this surface aerophilicity and the potential ozonation application for industrial wastewater treatment are both demonstrated.