标题:Photooxidation of arsenic(III) to arsenic(V) on the surface of kaolinite clay作者:Ding, Wei; Wang, Yajie; Yu, Yingtan;Zhang, Xiangzhi;Li, Jinjun; Wu,Feng来源出版物:JOURNAL OF ENVIRONMENTAL SCIENCES-CHINA 卷:36页:29-37 DOI:10.1016/j.jes.2015.03.017 出版年:OCT 1 2015
摘要:As one of the most toxic heavy metals, the oxidation of inorganic arsenic has drawn great attention among environmental scientists. However, little has been reported on the solar photochemical behavior of arsenic species on top-soil. In the present work, the influencing factors (pH, relative humidity (RH), humic acid (HA), trisodium citrate, and additional iron ions) and the contributions of reactive oxygen species (ROS, mainly HOU and HO2 center dot/O-2(center dot-)) to photooxidation of As(III) to As(V) on kaolinite surfaces under UV irradiation (lambda = 365 nm) were investigated. Results showed that lower pH facilitated photooxidation, and the photooxidation efficiency increased with the increase of RH and trisodium citrate. Promotion or inhibition of As(III) photooxidation by HA was observed at low or high dosages, respectively. Additional iron ions greatly promoted the photooxidation, but excessive amounts of Fe2+ competed with As(III) for oxidation by ROS. Experiments on scavengers indicated that the HOU radical was the predominant oxidant in this system. Experiments on actual soil surfaces proved the occurrence of As(III) photooxidation in real topsoil. This work demonstrates that the photooxidation process of As(III) on the soil surface should be taken into account when studying the fate of arsenic in natural soil newly polluted with acidic wastewater containing As(III).
入藏号:WOS:000362983500004
文献类型:Article
语种:English
作者关键词:Photochemical oxidation, Arsenic speciation, Soil clay minerals, Iron species, Hydroxyl radical
扩展关键词:PHOTOCATALYTIC OXIDATION; PHOTOCHEMICAL OXIDATION; HYDROXYL RADICALS; HUMIC-ACID; WATER; IRON; PHOTOLYSIS; SPECIATION; COMPLEXES; SOILS
通讯作者地址:Zhang, Xiangzhi;Chinese Acad Sci, Shanghai Inst Appl Phys, Shanghai Synchrotron Radiat Facil, Shanghai 201204, Peoples R China.
电子邮件地址:dingweidinghan@163.com; zhangxiangzhi@sinap.ac.cn; fengwu@whu.edu.cn
地址:
[Ding, Wei; Wang, Yajie; Yu, Yingtan; Li, Jinjun; Wu, Feng] Wuhan Univ, Sch Resources & Environm Sci, Hubei Key Lab Biomass Resource Chem & Environm Bi, Wuhan 430079, Peoples R China.
[Zhang, Xiangzhi] Chinese Acad Sci, Shanghai Inst Appl Phys, Shanghai Synchrotron Radiat Facil, Shanghai 201204, Peoples R China.
研究方向:Environmental Sciences & Ecology
ISSN:1001-0742
eISSN:1878-7320
影响因子(2014):2.002