Development and application of catalysts for catalytic ozonation of Cl-VOCs at low temperature: A comprehensive review

Abstract

Chlorinated volatile organic compounds (Cl-VOCs) are highly toxic and difficult to degrade. Unregulated release of pollutants presents a grave danger to both the health of humans and the natural environment. Catalytic ozonation is a low-cost and energy-efficient method to degrade Cl-VOCs. Treating readily volatile, highly toxic, and hardly degradable Cl-VOCs required a catalyst with high activity and resistance to chlorine. In this paper, recent advances in the catalytic ozonation of Cl-VOCs at low temperatures are systematically reviewed, including single Cl-VOCs and gas mixtures with Cl-VOCs. The microstructure, morphology, active components, support materials, surface acidity, oxygen vacancy, water and chlorine resistance of various catalysts for catalytic ozonation of Cl-VOCs are thoroughly discussed. It is possible to regulate surface acidity and oxygen vacancy density by Cu and Ce doping and vacuum drying treatment. The hollow structure, nanorod structure, and strong electronic metal–metal interaction (EMMI) coordination structures enhance catalyst chlorine resistance. It is emphasized that the doping of Ce on Mn-based catalysts can simultaneously modulate the catalyst surface acidity and oxygen vacancy, and enhance the chlorine resistance. Finally, the challenges of catalytic ozonation of Cl-VOCs are presented, and suggestions are provided for the future design of catalysts for catalytic ozonation by Cl-VOCs.