Hydrothermal oxidation of organochlorines

Abstract
The hydrothermal oxidation of four organochlorines (perchloroethylene, 1,1,1 trichloroethane, trichloroethylene and dichloromethane) was studied. This study aims at determining the influence of various parameters and the optimal conditions for obtaining the best oxidation yield in the degradation process. The factors studied were reaction temperature, initial substrate concentration, reaction time, agitation speed and volume of the solution in the reactor vessel. The tests were conducted following the methodology of experimental design. The results obtained show that these compounds are degraded rather easily in the working conditions. The degradation efficiency can reach 98% of the total organic carbon and 99.9% of the initial substrate concentration. The temperature and the initial substrate concentration are the most influential factors on the oxidation process. The reaction time and the volume of the solution have a less interesting influence on the degradation yield in the experimental areas. Formic acid and methanol are the byproducts found in the final effluents. Their concentrations decrease considerably when the reaction temperature is higher. The chlorine is found essentially in the Cl- form.