Photodegradation of bisphenol A in Fe（Ⅲ）-oxalate complexes solution

• Published in: Journal of environmental sciences (China) Vol. 18; no. 4; pp. 771 - 776
• Main Author: ZHAN Man-jun YANG Xi XIAN Qi-ming KONG Ling-ren
• Format: Journal Article
• Language: English
• Published: 2006
• Subjects: 光致氧化; 光降解作用; 反应氧; 环境污染化学; 草酸盐
• ISSN: 1001-0742; 1878-7320

The aqueous photodegradation of bisphenol A （BPA） in the presence of Fe（Ⅲ）-oxalate complexes （Fe（Ⅲ）-Ox）, which are common compositions of natural water, was investigated in this study. BPA underwent rapid indirect photolysis in Fe（Ⅲ）-Ox solution under simulated solar irradiation, proceeding pseudo-first-order kinetics. The photolysis rate increased with decreasing pH or initial BPA level and increasing Fe（Ⅲ）/oxalate concentration ratio. Hydroxyl radicals （·OH）, which were generated from the photochemical processes of Fe（Ⅲ）-Ox complexes and contributed to the photooxidation of BPA, were determined by molecular probe and electron spin resonance （ESR） methods with the steady-state concentration of 2.56 × 10^-14 mol/L. Superoxide anion radical （O2^·-） was considered as the precursor of. OH and qualitatively determined by adding nitro blue tetrazolium as well as ESR experiments. Based on the structural analysis of the intermediate photoproducts of BPA in Fe（Ⅲ）-Ox complexes solution, the possible degradation pathways of BPA were proposed, involving ·OH addition, alkyl scission and alky oxidation. The results indicate that the photochemical reactivity of Fe（Ⅲ） may affect the environmental fate of BPA in natural water significantly.