文献类型：期刊文献

英文题名：Mechanism of uranium release from uranium mill tailings under long-term exposure to simulated acid rain: Geochemical evidence and environmental implication

作者：Yin, Meiling[1];Sun, Jing[2];Chen, Yongheng[1,3];Wang, Jin[1,4];Shang, Jianying[5];Belshaw, Nick[4];Shen, ChuanChou[6,7];Liu, Juan[1,4];Li, Huosheng[1];Linghu, Wensheng[8];Xiao, Tangfu[1];Dong, Xinjiao[9];Song, Gang[1,3];Xiao, Enzong[1];Chen, Diyun[1,3]

机构：[1]Guangzhou Univ, Sch Environm Sci & Engn, Guangzhou 510006, Guangdong, Peoples R China;[2]Univ Western Australia, Sch Earth Sci, Perth, WA 6009, Australia;[3]Guangdong Prov Key Lab Radionuclides Pollut Contr, Guangzhou 510006, Guangdong, Peoples R China;[4]Univ Oxford, Dept Earth Sci, Oxford OX1 3AN, England;[5]China Agr Univ, Coll Resources & Environm Sci, Beijing 100193, Peoples R China;[6]Natl Taiwan Univ, Dept Geosci, Taipei 10617, Taiwan;[7]Natl Taiwan Univ, Res Ctr Future Earth, Taipei 10617, Taiwan;[8]Shaoxing Univ, Coll Chem & Chem Engn, Shaoxing 312000, Peoples R China;[9]Wenzhou Univ, Sch Life & Environm Sci, Wenzhou 325027, Peoples R China

年份：2019

卷号：244

起止页码：174

外文期刊名：ENVIRONMENTAL POLLUTION

收录：SCI-EXPANDED(收录号：WOS:000452940700020)、、EI(收录号：20184506050444)、Scopus(收录号：2-s2.0-85056182962)、WOS

基金：This work was jointly supported by the National Natural Science Foundation of China (No.41773011; 41501232; 41573008; 41873015; 41573119; U1612442), the Natural Science Foundation of Guangdong Province, China (2017A030313247; 2015A030313512), the Environmental Protection Ministry of Public Welfare Research Projects (201509051), Public Welfare Research Project of Zhejiang Province, China (LGF18E080013), and the Guangzhou University's 2017 training program for young top-notch personnel (BJ201709), and High Level University Construction Project of Guangdong Province (Regional Water Environment Safety and Water Ecological Protection). The Sponsorship from the China Scholarship Council (University of Oxford) granted to Jin Wang was acknowledged. The help from Dr. Jianying Qi from South China Institute of Environmental Sciences, Ministry of Ecology and Environmental with uranium measurement was highly appreciated.

语种：英文

外文关键词：Uranium; Uranium mill tailings; Leaching test; Acid rain

外文摘要：To date, there is not sufficient knowledge to fully understand the occurrence, transport and fate of residual uranium (U) from uranium mill tailings (UMT). Herein this study investigated different U release behaviors from natural UMT (without grinding) under four simulated acid rain (pH = 2.0-5.0) compared with controlled scenario (pH = 6.0) for 25 weeks. The results showed that the most notable U release was observed from UMTpH2.0, followed by UMTpH3.0 whereas a nonlinear relationship between pH and U release was observed from UMTpH4.0-6.0. The divergence of U release behaviors was attributed to the presence of minerals such as calcite and clinochlore. Autunite, a secondary mineral formed after leaching, might regulate U release in UMTpH3.0-6.0. Fick theory model revealed the shift of U release mechanism from surface dissolution to diffusion transport for UMTpH2.0, UMTpH3.0 and UMTpH5.0 at varied stage, whereas UMTpH4.0 and UMTPH6.0 displayed univocal dissolution and diffusion mechanism, respectively. This study highlights the necessity of performing long-term leaching tests to detect the "shift event" of leaching kinetics and to better understand the mechanism of U release influenced by mineralogy of the natural UMT under simulated acid rain conditions, which is conducive to developing UMT management strategies to minimize the risk of U release and exposure. (C) 2018 Elsevier Ltd. All rights reserved.