Catalytic oxidative degradation of 4-chlorophenol: Effect of operating parameters and prediction of intermediates/by-products.

The presence of chlorophenols (CP) in industrial wastewater 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 Fenton reaction at an initial pH, Fe²⁺ concentration, and H₂O₂ to Fe²⁺ molar ratio of 3.0, 1.26 mM and 20, respectively which were found to increase to 79 and 55%, respectively when Cu²⁺ was also added with Fe²⁺ during modified Fenton process. © 2017 American Institute of Chemical Engineers Environ Prog, 36: 1734-1742, 2017 [ABSTRACT FROM AUTHOR]