高等学校化学学报2016，Vol.37Issue(8)：1499-1508,10.DOI:10.7503/cjcu20160156
紫外光致氯生水合电子对全氟辛酸的降解
Degradation of Perfluorooctanoic Acid by UV/Chloride Process†
摘要
Abstract
Based on the characteristic of perfluorooctanoic acid( PFOA) that it is vulnerable to be nucleophile attacked, we developed a new method for the degradation of PFOA in aqueous phase with chloride as a media-tor. In this study, 185 nm ultraviolet photolysis of chloride leads to the generation of hydrated electrons, which contribute to the defluorination of PFOA. Chloride, ultraviolet, and anaerobic environment are all the necessa-ry factors to ensure the effective degradation of PFOA. In this system, when the concentration of PFOA is 0. 03 mmol/L, the optimal reaction conditions are cCl-/cPFOA=10. 0, pH=10. 0, with temperature being 25 ℃. Under these conditions, the degradation and defluorination rates of PFOA after 23 h’ s reaction are 99. 6% and 65. 0%, respectively. Kinetic analysis indicated that the decomposition of PFOA fits the first order model with a rate constant of 6. 3 ×10-3 min-1 . The degradation products are fluorinion, perfluorinated carboxylic acid with short-carbon-chains, formic acid, and acetic acid. According to the degradation products, we proposed two major degradation pathways of PFOA: direct cleavage of C—F bonds and C—C bonds due to the attack by hydrated electrons;and decarboxylating by ultraviolet irradiation and defluorinate by hydrolysis. This method is of great significance to eliminate the PFOA in wastewater.关键词
全氟辛酸/水合电子/氯离子/185nm紫外光Key words
Perfluorooctanoic acid/Hydrated electron/Chloride/185 nm Ultraviolet分类
化学化工引用本文复制引用
郭睿,张超杰,张庚,周琪..紫外光致氯生水合电子对全氟辛酸的降解[J].高等学校化学学报,2016,37(8):1499-1508,10.基金项目
国家自然科学基金(批准号:21177094,41271465)资助.? Supported by the National Natural Science Foundation of China(Nos.21177094,41271465) （批准号:21177094,41271465）
