Environmental Science Research Institution, College of Environment Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
J Hazard Mater. 2010 Jul 15;179(1-3):1143-6. doi: 10.1016/j.jhazmat.2010.02.030. Epub 2010 Feb 17.
The photochemical decomposition of perfluorooctanoic acid (PFOA) in aqueous periodate (IO(4)(-)) was investigated under two types of low-pressure mercury lamps: one emits at 254nm light (UV light) and the other emits both 254 nm and 185 nm light (VUV light). PFOA decomposed efficiently under VUV light irradiation while it decomposed poorly under UV light irradiation. The addition of IO(4)(-) significantly increased the rate of decomposition and defluorination of PFOA irradiated with UV light whereas it decreased both processes under VUV irradiation. Reactive radical (IO(3)) generated by photolysis of IO(4)(-) initiated the oxidation of PFOA in UV process. Aquated electrons (e(aq)(-)), generated from water homolysis, scavenged IO(4)(-) resulting in decrease of reactive radical species production and PFOA decomposition. The shorter-chain perfluorocarboxylic acids (PFCAs) formed in a stepwise manner from long-chain PFCAs.
过碘酸盐（IO 4 (-) ）存在下全氟辛酸（PFOA）的光化学分解在两种低压汞灯中进行：一种发出 254nm 光（UV 光），另一种发出 254nm 和 185nm 光（VUV 光）。PFOA 在 VUV 光照射下有效分解，而在 UV 光照射下分解不良。IO 4 (-) 的添加显著提高了 UV 光照射下 PFOA 的分解和脱氟速率，而在 VUV 照射下则降低了这两个过程。IO 4 (-) 的光解产生的反应性自由基（IO 3 (-) ）引发了 UV 过程中 PFOA 的氧化。水均裂产生的水合电子（e(aq)(-) ）捕获 IO 4 (-) ，导致反应性自由基物种的产生和 PFOA 分解减少。短链全氟羧酸（PFCAs）从长链 PFCAs 逐步形成。
