Degradation of endocrine‐disrupting chemicals using various sulfate radical activation methods: kinetics and mechanism

Abstract

AbstractBACKGROUNDMost studies have focused on the degradation of endocrine‐disrupting chemicals using persulfate activation processes. Therefore, the current study compares various sulfate radical activation processes in an aqueous solution of a mixture of diethyl phthalate, butylparaben and bisphenol A that are present in water and wastewater. The effects of initial persulfate dose and pH variation, the effect of concentration of target endocrine‐disrupting chemicals and degradation efficiency under various processes were studied. Additionally, the toxicity and cost estimation of the systems were also examined.RESULTSThe results showed pseudo‐first‐order kinetics with maximum degradation efficiency of 99% for 1 mg L−1 at pH 7, 2.5 mmol L−1 persulfate dose, 450 W power in 60 min for UV‐activated persulfate oxidation process. A quenching experiment highlights the dominance of both sulfate and hydroxyl radicals in the degradation of mixtures of diethyl phthalate, butylparaben and bisphenol A in an aqueous solution. The transformative products identified using gas chromatography–mass spectrometry were monohydroxylated structures that decompose to form organic acids, indicating efficient degradation capacity with minimal toxicity. Further, the sono‐activated persulfate oxidation process was found to be cost‐effective at 1 mg L−1 with 95% degradation efficiency.CONCLUSIONIt is concluded that an increase in the concentration of target compounds decreases the efficiency of degradation under various activation processes. pH 3 and pH 7 favor thermal and sono‐activated and UV‐activated processes, respectively. Toxicity evaluation shows minimal harm to non‐target species Daphnia magna for all activation processes. These findings can be useful for on‐field application for the degradation of chemicals in mixtures. © 2023 Society of Chemical Industry.