Destruction of aromatic pollutants by UV light catalyzed oxidation with hydrogen peroxide

Abstract

Abstract Toxic and hazardous compounds are often present in water at low concentrations, which can make their removal difficult and costly by conventional treatment processes. A promising method for destroying pollutants in water is ultraviolet (UV) catalyzed oxidation by hydrogen peroxide. The effectiveness of this process was determined for typical aromatic compounds including benzene, toluene, chlorobenzene, phenol, 2‐chlorophenol, 2,4‐dichlorophenol, 2,4,6‐trichlorophenol, dimethyl phthalate, and diethyl phthalate. The reactions were conducted in a quartz annular reactor equipped with a low‐pressure mercury lamp. Of the aromatics studied, reaction rates were fastest with 2,4,6‐trichlorophenol and slowest with the phthalates. Analyses of reacted samples by HPLC and GC/MS indicated that the aromatics formed many intermediates that could be destroyed by extending the treatment time. An empirical rate expression was developed to correlate the results.