场地土壤中有效态砷的稳定化处理及机理研究_卢聪.pdfVIP

中国环境科学 2013,33(2) ：298~304 China Environmental Science 场地土壤中有效态砷的稳定化处理及机理研究 1,2 1 1* 2 1 卢 聪 ,李青青 ,罗启仕 ,刘莉莉 ,张长波 (1.上海市环境科学研究院,上海 200233 ；2.华东理工大学资 源与环境工程学院,上海 200237) 摘要：分别以生石灰和亚铁盐作为辅助剂与稳定剂对 2 种砷污染的土壤进行稳定化处理,通过化学浸出、形态及结构研究,揭示土壤中有 效砷的稳定效率和机理.结果表明,外源铁添加量与土壤砷含量(Fe/As)的物质的量比达到6:1~8:1,CaO 投加比例为0.05%~0.1%(w/w)时,土壤 中有效态砷的稳定效率超过 85%.土壤有效砷的稳定化处理主要是将砷从非专性吸附态和专性吸附态转化为弱结晶的铁铝或铁锰水化氧 化物结合态、结晶铁铝或铁锰水化氧化物结合态.稳定处理后 2 种污染土均有新物相羟砷铜矿(As Cu H O )生成. 2 5 4 12 关键词：土壤；砷；稳定化；形态变化；X 射线衍射 中图分类号：X703.5 文献标识码：A 文章编号：1000-6923(2013)02-0298-07 Stabilization treatment of available arsenic in contaminated soils and mechanism studies. LU Cong1,2 1 , LI Qing-qing , LUO Qi-shi1*, LIU Li-li2 , ZHANG Chang-bo1 (1.Shanghai Academy of Environmental Sciences, Shanghai 200233, China; 2.School of Resources and Environmental Engineering of East China University of Science and Technology, Shanghai 200237, China). China Environmental Science, 2013,33(2)：298~304 Abstract ：Lime and Ferrous salt was used as the auxiliary agent and stabilizing agent to treat two arsenic contaminated soils. Following chemical leaching test, the stabilizing effectiveness and mechanism of available arsenic on treated soil were shown using morphology and structure analysis. Importantly, the stabilizing efficiency of arsenic for the two types of soils were both over 85% when the ratio of exogenous Fe and soil As (mol/mol) was 6:1~8:1 and the dosing ratio of CaO was 0.05% ~ 0.1% (w/w). The stabilization of arsenic in soil was attributed mainly to two following reasons: (1) arsenic was trans