稳定化的零价Fe,FeS,Fe3O4纳米颗粒在土壤中的固砷作用机理

被引:20
作者
张美一
潘纲
机构
[1] 中国科学院生态环境研究中心,环境水质学国家重点实验室
关键词
砷; 固定; 铁; 纳米颗粒; 土壤污染; 土壤修复;
D O I
暂无
中图分类号
S153 [土壤化学、土壤物理化学];
学科分类号
摘要
砷是一种广泛存在于土壤和地下水中的污染物.虽然多种铁基材料已被用于受污染土壤中砷的固定,但是关于稳定化的铁系纳米颗粒在该方面的研究鲜见报道.本文研究了3种经淀粉固定的铁系纳米颗粒(零价Fe,FeS,Fe3O4)对两种典型砷污染土壤(果园土壤、靶场土壤)的固砷作用.为了检测纳米颗粒对砷的去除效果,实验中采取了不同的Fe/As摩尔比(5:1~100:1)和接触时间(3或7d).土壤中砷的生物活性和浸出率分别用生理原理提取法(physiologically based extraction test,PBET)和毒性浸出程序(toxicity characteristic leaching procedure,TCLP)方法表征.在实验时间为3d、Fe/As摩尔比为100:1的实验中,果园砂质土壤中砷的生物活性从最初的71.3%±3.1%分别降至30.9%±3.2%(零价Fe)、37.6%±1.2%(FeS)和29.8%±3.1%(Fe3O4);靶场土壤中砷的浸出率从初始0.51%±0.11%分别降至0.24%±0.03%(零价Fe)、0.27%±0.04%(FeS)和0.17%±0.04%(Fe3O4).3种纳米颗粒中Fe3O4的固砷效率最高.比较两种土壤,可以看出该处理方法更适用于铁含量较低、砷初始浸出率较高的果园土壤.结果表明,对于砷污染的贫铁土壤、沉积物和固废等,环境友好的铁系纳米颗粒是十分有效的固砷材料.
引用
收藏
页码:3637 / 3644
页数:8
相关论文
共 17 条
[11]  
Decreasing arsenic bioaccessibility with iron amendments.Doctor Dissertation .2 Subacz J L. . 2004
[12]  
Nanoscale Iron Particles for Environmental Remediation: An Overview[J] . Wei-xian Zhang.Journal of Nanoparticle Research . 2003 (3)
[13]  
Treatment of Arsenic-Contaminated Soils. II: Treatability Study and Remediation[J] . Joel Miller,Humayoun Akhter,Frank K. Cartledge,Mary McLearn.Journal of Environmental Engineering . 2000 (11)
[14]  
Treatment of Arsenic-Contaminated Soils. I: Soil Characterization[J] . Humayoun Akhter,Frank K. Cartledge,Joel Miller,Mary McLearn.Journal of Environmental Engineering . 2000 (11)
[15]  
Arsenic in the Soil Environment: A Review[J] . E. Smith,R. Naidu,A.M. Alston.Advances in Agronomy . 1998
[16]  
The mechanism of anion adsorption on iron oxides: Evidence for the bonding of arsenate tetrahedra on free Fe(O, OH) 6 edges[J] . Alain Manceau.Geochimica et Cosmochimica Acta . 1995 (17)
[17]  
Geometry of sorbed arsenate on ferrihydrite and crystalline FeOOH: Re-evaluation of EXAFS results and topological factors in predicting sorbate geometry, and evidence for monodentate complexes[J] . Glenn A. Waychunas,James A. Davis,Christopher C. Fuller.Geochimica et Cosmochimica Acta . 1995 (17)