Kinetics of vapor destruction of 1,4-dichlorobenzene in a dielectric barrier discharge in oxygen
1,4-Dichlorobenzene (1,4-DCB) is a carcinogen. Therefore, the purification of gases from the vapor of this substance is an urgent task. In this work, we studied the vapor decomposition of 1,4-dichlorobenzene under the action of a dielectric barrier discharge (DBD) of atmospheric pressure in oxygen. The range of specific discharge powers was 0.6–1.7 W/cm3, concentrations of 2,4-DCB was 0.076–0.382 mg/l, and gas flow rate was 1–3 cm3/s. The concentrations of 1,4-DCB and its decay products were measured using chromatography, spectrophotometry, fluorometry, and some others. It was found that the kinetics of decomposition (the dependence of the concentration of 1,4-DCB on the gas residence time) obeys the first-order kinetic equation with a rate constant of about 0.13 s−1. The decomposition products were carboxylic acids, aldehydes, CO2, and Cl2. CO2 yield is 75% of total carbon content in system. The decomposition process is accompanied by the formation of a polymer film on the reactor walls. The composition of the film was characterized by the EDX method and FTIR. The elemental composition of the film was C:O:Cl = 1:2.1:0.1. FTIR spectra showed that the film contains a significant amount of functional groups of carboxylic acids. The results demonstrated that DBD is an effective tool to remove 1,4-DCB. The process is characterized by the following indicators. The maximum degree of decomposition reaches 90%. The energy yield of decomposition is 2.7 × 10−3 molecules per 100 eV, and specific input energy is 15 kJ/l.
Publisher URL: http://link.springer.com/article/10.1007/s13762-020-02703-2