摘要
采用动态风化模拟实验方法对来自广东某Tl污染区的硫铁矿矿样进行了2a左右持续的氧化淋滤实验,研究了硫铁矿酸化趋势及毒害金属元素铊Tl从源头向环境长期释放迁移的特征,探讨了硫铁矿酸化及Tl释放迁移的机制.结果表明:含碳酸盐硫铁矿暴露后,排放液pH值随时间呈缓慢波段下降趋势,较长时期内排放液pH>5.伴随硫铁矿酸化过程,Tl具特有的释放迁移特征.硫铁矿一旦暴露Tl就开始释放,且具强的迁移性,随后伴随风化进程呈波段减弱.在pH>5的环境中,Tl释放迁移受pH值的影响不同于酸性(pH<5)环境中,pH值降低对Tl的释放迁移没有促进作用,滤液中Tl的浓度与pH值呈正相关,还原环境有助于Tl的释放迁移.
The trend of acid generation and characterization of long term thallium release from one pyrite with carbonate in Guangdong were studied using kinetic weathering test in humidity cell.Results of leaching tests lasting about 2 years showed that the pH of leachates decreased slowly with time and maintained more than 5 for long time after pyrite exposure to air.Thallium released and showed high mobilization once pyrite exposed in air and than thallium release decreased wave-likely with weathering on.The pH of leachate above 5 had different impact on thallium release from pH5.When pH5,lower pH could not cause more thallium releasing,concentration of dissolved thallium in leachate was positively with pH and reductive condition was good for thallium releasing.
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2012年第6期1026-1031,共6页
China Environmental Science
基金
国家自然科学基金委-广东省人民政府联合基金资助项目(u0633001)
国家自然科学基金资助项目(41073003)
