Plasma Purification of Halogen Volatile Organic Compounds

The halogen volatile organic compound (VOC) is a common industrial pollutant, mainly including trichloroethylene, dichloromethane, trichloroacetic acid, chloro-fluoro-carbons, carbon tetrachloride, trihalomethans, chlorodifuoromethanes, hydrofluorocarbons, and some other fluor alkaline, ether, and amine. The halogen VOCs have reproductive toxicity, immunotoxicity, and neurotoxicity. The traditional methods for treating them include masking method, dilution method, chemical oxidation method, incineration method, UV oxidation method, photocatalytic oxidation method, absorption method, and biological method. In this paper, advantages and disadvantages of traditional methods have been studied and analyzed. A new plasma technology has been put forward, which has the advantage of the rapid reaction to ambient temperature, wide applications, system compactness, simplicity of operation and short residual time, and the plasma technology is especially appropriate for the decomposition of VOCs. At present, as for the control of VOCs, the plasma technology has drawn much attention as an energy-saving technology. In this paper, the equipment for the decomposition of halogen VOCs has been analyzed, including the plasma rectors, power characteristics, operation conditions, and the decomposition mechanisms of C₂HCl₃, CH₂Cl₂, C₂H₃Cl₃, CCl₄, CHCl₃, CF₄, C₂F₆, and SF₆ have been investigated and concluded. Finally, it is concluded that the combination of the plasma technology with traditional methods would be main direction of study in the future.