Application of the photo-Fenton process to the mineralization of phthalic anhydride in aqueous medium

The oxidation of phthalic anhydride, a chemical widely used as plasticizer, was studied in aqueous medium of pH 3 by the photochemical advanced oxidation process photo-Fenton using UV irradiation. This process generates, in a catalytic way, the hydroxyl radicals, a powerful oxidant species, for the oxidation of organic pollutants. The kinetics of the oxidative degradation of phthalic anhydride and that of the solution mineralization was investigated through the effect of some operating parameters such as the ratio R = [H2O2]/[Fe3+] and the initial catalyst concentration. The values of R = 40 and Fe3+ ion (catalyst) concentration of 0.1 mM were found as optimum operating parameters. Mineralization of phthalic anhydride aqueous solution under the optimal conditions was followed by the total organic carbon (TOC) analysis and a high mineralization degree of 98.7% was determined for a treatment time of 2 h.