Degradation of Several Chlorophenols Using Advanced Oxidative Processes: Major and Minor Products

This study focuses on finding direct evidence of oxidative degradation of chlorophenols. The aim of the study was distinguishing major and minor degradation products. Several chlorophenols with different numbers of chloride substituents (2-chlorophenol, 2,4-dichlorophenol, and 2,4,5-trichlorophenol) were chosen for a thorough study. UV photolysis, Fenton, and photo-Fenton processes were tested as advanced oxidative processes. Photo-Fenton appeared to result in higher conversions of mono- and dichlorophenols. Conversions of trichlorophenol were comparable for all the processes under this study. Formic and acetic acids were shown to be the major products. Their formation was confirmed by 1H NMR spectroscopy. Other possible products are minor and are formed in negligible concentrations. The degradation methods can be considered harmless techniques of inactivating the chlorophenols, leading to the formation of products of low toxicity.