铁铈氧化物对土壤As(Ⅴ)和P的稳定化效果  

Stabilizing Effects of Fe-Ce Oxide on Soil As (Ⅴ) and P

作　　者：林龙勇[1,2] 阎秀兰 杨硕[3] LIN Long-yong;YAN Xiu-lan;YANG Shuo(Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China;Institute of Eco-environment & Soil-remediation,Guangdong Provincial Academy of Environmental Science,Guangzhou 510045,China;School of Environment,Tsinghua University,Beijing 100084,China)

机构地区：[1]中国科学院地理科学与资源研究所,北京100101 [2]广东省环境科学研究院生态环境与土壤修复研究所,广州510045 [3]清华大学环境学院,北京100084

出　　处：《环境科学》2019年第8期3785-3791,共7页Environmental Science

基　　金：国家自然科学基金项目(41571309);广州市科技计划项目(201804010424)

摘　　要：本文以铁铈氧化物(Fe-Ce,FC)为研究对象,评估其对中国3种典型砷(As)污染土壤的稳定化修复效果,并通过电子扫描显微镜能散X线分析仪(SEM-EDS)和X射线光电子能谱仪(XPS)等光谱学技术探索FC对As(Ⅴ)的微观吸附特征.结果表明,FC能使土壤毒性浸出As含量显著降低84. 1%~98. 3%,且在碱性土壤中表现出较强的高p H适应性,能显著增加吸附态As(F1+F2)向水合铁铝氧化物结合态(F3+F4)的稳定化. FC能使不同类型土壤的有效态P含量显著下降47. 13%~60. 32%,不仅能缓解P竞争土壤As(Ⅴ)吸附位点,而且能有效预防周边水体的面源污染.通过SEM-EDS和XPS分析,发现As(Ⅴ)吸附产物表面均检测到Fe、Ce和As这3种元素,且As主要吸附于Fe原子表面. FC在我国土壤砷污染稳定化修复领域具有较好地应用前景.The mining and smelting of arsenic-containing metal minerals,and the large-scale use of chemicals and pesticides,has resulted in the widespread pollution of soils in southwestern and southern China. In this study,the stabilizing effect of Fe-Ce oxide( FC) on three representative arsenic-contaminated soils was evaluated. The microscopic adsorption characteristics of FC and As(Ⅴ)were explored by scanning electron microscopy and energy disperse spectroscopy( SEM-EDS) and X-ray photoelectron spectroscopy(XPS). The results showed that FC can significantly reduce arsenic concentrations by 84. 1%-98. 3% during the Toxicity Characteristic Leaching Procedure(TCLP),and showed strong p H adaptability in alkaline soil. It efficiently transformed(non-)specifically sorbed arsenic(F1 + F2) into hydrous oxides phases of Fe and Al( F3 + F4). FC also significantly reduced available P by47. 13%-60. 32% in different types of soil. FC can not only release As(Ⅴ) adsorption sites occupied by P in soils,but also effectively prevents non-point source pollution of the surrounding water. SEM-EDS and XPS analysis detected Fe,Ce,and As on the surface of As(Ⅴ) adsorption products,and As was mainly adsorbed on the surface of Fe atoms. The results of this study provide a scientific basis for soil arsenic stabilization in China.

关 键 词：铁铈氧化物 土壤 砷 稳定化 光谱学技术 

分 类 号：X53[环境科学与工程—环境工程]