期刊
ENVIRONMENTAL POLLUTION
卷 243, 期 -, 页码 637-644出版社
ELSEVIER SCI LTD
DOI: 10.1016/j.envpol.2018.09.023
关键词
Tetrapod ZnO; Defluorination; Poly and per-fluoroalkyl substances (PFASs).; 5:3 FTCA; 5:2 FTCA; PFOA
资金
- Higher Committee for Education Development in Iraq
- Chinese Oversea Scholarship
- American Chemical Society Petroleum Research Fund [55315ND10]
Occurrence of per- and poly-fluoroalkyl substances (PFASs) in the environment and biota has raised a great concern to public health because these compounds are persistent, bioaccumulative, and toxic. Biodegradation of polyfluoroalkyl substances, particularly long-chain fluorotelomer-based products, can lead to production of various short-chain PFASs, with 5:3 fluorotelomer carboxylic acid (referred as 5:3 FTCA hereafter) as a dominant polyfluoroalkyl metabolite. Perfluoroalkyl acids, particularly perfluorooctanoic acid (PFOA), are toxic and current removal methods are not cost-effective. This study reports the photodegradation of 5:3 FTCA and PFOA using ZnO as a photocatalyst under neutral pH and room temperature conditions. Under long UV wavelength (365 nm), both tetrapod and commercial ZnO can photodegrade 5:3 FTCA. Five removal products-perfluorohexanoic acid, perfluoropentanoic acid, perfluorobutyric acid, 5:2 fluorotelomer carboxylic acid (5:2 FTCA), and inorganic fluoride-were identified, with PFBA and F- as dominant end products. SEM and XPS high-resolution scans on the surface of the utilized ZnO showed less units of CF2 than that in 5:3 FICA, supporting occurrence of photo degradation of 5:3 FTCA by ZnO. Defluorination of PFOA was not observed with ZnO only, but at pH 5 and in the co-presence of Fe-citrate. PFOA defluorination increased from 0.93% after 3 days of UV light exposure to 3.9% after additional 135 h under direct sunlight exposure. To the authors' best knowledge, this is the first report studying ZnO-catalyzed photodegradation of 5:3 FICA, and examining the Fe co-addition for PFOA defluorination. (C) 2018 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据