The Influence of the Structure of Organochlorine Compounds on Their Decomposition Process in a Dielectric Barrier Discharge

Abstract

The decomposition efficiency of C2HCl3 and CHCl3 in a barrier discharge is very different, even though these compounds differ little in chemical composition. In both compounds, there are three chlorine atoms and one hydrogen atom. The difference between them is the presence of one carbon atom in CHCl3 and two carbon atoms connected by a double bond in C2HCl3 and the higher polarizability of C2HCl3. The polarizability of C2HCl3 is 10.21 Å3 and that of CHCl3 is 8.39 Å3. As a result of these differences, the C2HCl3 conversion was two to three times higher than the CHCl3 conversion. The main product of CHCl3 decomposition containing chlorine was ClO2, while Cl2, COCl2, HCl, CCl4, and Cl− were formed in smaller amounts. The main products of C2HCl3 decomposition, which contain chlorine, were COCl2, HCl, and Cl−. CCl4 was not formed. Cl2 and ClO2 were formed in smaller amounts. Pathways of C2HCl3 and CHCl3 decomposition are shown in this paper. The process was carried out at low power (0.2–0.8 W) in air. The gas flow was 10 L/h, and the concentration of the decomposed compound was 0.4%. The volume of the gas space of the reactor (plasma zone) was 27 cm3.