Benzophenone-3 degradation via UV/H2O2 and UV/persulfate reactions

Young-Min Lee; Gowoon Lee; Kyung-Duk Zoh

doi:10.1016/j.jhazmat.2020.123591

Benzophenone-3 degradation via UV/H₂O₂ and UV/persulfate reactions

J Hazard Mater. 2021 Feb 5:403:123591. doi: 10.1016/j.jhazmat.2020.123591. Epub 2020 Aug 2.

Authors

Young-Min Lee¹, Gowoon Lee¹, Kyung-Duk Zoh²

Affiliations

¹ Institute of Health and Environment, Seoul National University, Seoul, South Korea.
² Department of Environmental Health Sciences, School of Public Health, Seoul National University, Seoul, South Korea. Electronic address: zohkd@snu.ac.kr.

PMID: 32795823
DOI: 10.1016/j.jhazmat.2020.123591

Abstract

The degradation of benzophenone-3 (BP3) in water via the UV/H₂O₂ and UV/persulfate (UV/PS) reactions was investigated. The degradation of BP3 exhibited pseudo-first-order kinetics in both reactions. The degradation efficiency of BP3 was higher in the UV/PS reaction than in the UV/H₂O₂ reaction. In both reactions, the observed rate constants (k_obs) of BP3 degradation were highest at pH 6 and increased linearly with increasing dosage of H₂O₂ and persulfate. The second-order rate constants of BP3 with •OH (k_{•OH_BP3}) and •SO₄^- (k_•SO4-_{_BP3}) were determined to be 1.09 (± 0.05) × 10¹⁰ and 1.67 (± 0.04) × 10⁹ M^-1 s^-1, respectively. The k_obs values of BP3 were affected by water components such as HCO₃^-, NO₃^-, Cl^-, and Br^- ions, as well as humic acid. Based on the identified transformation products (TPs), the degradation pathway of BP3 during both reactions was a hydroxylation reaction. The inhibition of bioluminescence in Vibrio fischeri due to BP3 and its TPs decreased more quickly in the UV/PS reaction than in the UV/H₂O₂ reaction. The results suggest that the UV/PS process is a better alternative to the UV/H₂O₂ process for removing BP3 and its toxicity in water.

Keywords: Oxybenzone; UV-AOP; byproducts; radicals; toxicity.

Publication types

Research Support, Non-U.S. Gov't