Catalytic Oxidative Degradation of 4-Chlorophenol: Effect of Operating Parameters and Prediction of Intermediates/By-Products

摘要

The presence of chlorophenols (CP) in industrial wastewa-ter is a major concern due to their microbial toxicity. The present study was performed to investigate the efficacy of advanced oxidation process (i.e., conventional and modified Fenton's process) for the degradation of 4-chlorophenol (4-CP) in an aqueous solution (concentration = 200 mg L~(-1)) under varying reaction conditions. The decomposition of 4-CP was confirmed by chemical oxygen demand (COD) reduction, total organic carbon (TOC) reduction, detection of low molecular weight carboxylic acids (such as oxalic, acetic, formic and malonic) and Cl~- concentration in the treated 4-CP aqueous solution. The maximum COD and TOC reductions were 74% and 42% after 30 min of Penton reaction at an initial pH, Fe~(2+) concentration, and H_2O_2 to Fe~(2+) molar ratio of 3.0, 1.26 mM and 20, respectively which were found to increase to 79 and 55%, respectively when Cu~(2+) was also added with Fe~(2+) during modified Fenton pro-cess.