Comparison on the formation and toxicity for chlorinated products during the oxidation of acetic acid (CH3COOH) by three widely used advanced oxidation processes (AOPs) at the presence of [formula omitted

Abstract

As a technology for industrial wastewater advanced treatment, there is a lack of relevant information the impacts of the treated effluents by advanced oxidation processes (AOPs) on ecological environment. Therefore, this study mainly compared the differences of the formation types and concentrations of chlorinated organic products（COPs）and active inorganic chlorine species (AICS) and toxicity changes in the oxidation of CH3COOH by three commonly used AOPs technologies as Fenton, ozone and electrochemical advanced oxidation process (EAOP) with the addition of Cl−. The results illustrate that in the EAOP process, trichloromethane (TCM) and Chloroacetic acids (CAAs) were the main COPs in the oxidation of CH3COOH by EAOP at 120 min. CCl4 was major COPs for the Fenton and ozone oxidation of CH3COOH, respectively. Through the algae growth inhibition experiment and the toxicity evaluation by using ECOTOX toxicity database, the toxicity of EAOP oxidation of CH3COOH to algae and fish were much higher than those from Fenton and ozone oxidation as the highest formation concentrations of inorganic by-products. Considering the toxic effects on the environment, when choosing the AOPs for the further treatment of wastewater containing Cl−, try to avoid the use of EAOP technology, and it is better to choose Fenton and ozone oxidation.