Experimental Study on In-Situ Decomposition of VOCs Using Microwave-Induced Metal Discharge

Purpose In recent years, haze has become a critical environmental issue. As a crucial precursor of haze, volatile organic compounds (VOCs) have become a major research focus. Methods In this study, microwave-induced metal discharge was developed for VOC decomposition. Toluene was used as the VOC model compound. Four types of metal strips were investigated for their decomposition efficiency of toluene using a microwave-induced metal discharge process. Results All discharges, regardless of the metal type, achieved a high decomposition efficiency of toluene [> 60% (mol/mol)]. In addition, the effects of reaction conditions such as metal strip weight, gas flow rate, microwave power, and gas initial concentration were studied to investigate the decomposition efficiency. The reaction conditions were optimized following a multi-factor orthogonal experiment. The weight of the metal strips and gas flow rate had greater impacts on the decomposition efficiency, whereas the microwave power had a moderate impact. The major reaction products were CO 2 , CO, O 3 and H 2 O. Both hydroxyl radicals and active oxygen atoms were very important for toluene oxidation. Conclusion This study offers an important reference for the development of new technology to support the decomposition of VOCs.