Treatment of aqueous dimethyl phythalate solution by fenton and photo-fenton processes

This study makes a comparison between Fenton and photo-Fenton processes to study the mineralization of aqueous dimethyl phthalate (DMP) solutions, which was chosen as the model phthalate ester. At [Fe²⁺] ₀:[H₂O₂]o ratio of 1:5 with initial Fe ²⁺ and H₂O₂ concentrations of 10 mM and 50 mM provided the best operation condition for the Fenton treatment of aqueous DMP solutions in terms of DMP (100%), COD (86%), and TOC (69%) removals. The rate of DMP degradation as well as COD and TOC abatements were increased by irradiation of Fenton's reaction with UV-C light (photo-Fenton process). At the end of the 60 min treatment period, practically total mineralization was achieved for photo-Fenton process at the [Fe²⁺]₀:[H₂O ₂]₀ ratios of 0.5:30 and 2:20. Results expressed as the percentage inhibition of the luminescence of the marine bacteria Vibrio fischeri showed that the inhibitory effect of DMP was reduced after Fenton and photo-Fenton treatments, thus these processes can be suggested as promising methods to detoxify aqueous DMP solution.