多硫化物修饰nZVI@BC对污染土壤中铬的稳定化:铬的生物可用性和稳定机制  

Chromium stabilization by polysulfide supported nZVI@biochar in contaminated soil:Cr bioavailability and stabilization mechanism

作　　者：陈劲松 王鑫 晏鑫尧 王晓科 马慧 蒲生彦 CHEN Jin-song;WANG Xin;YAN Xin-yao;WANG Xiao-ke;MA Hui;PU Sheng-yan(State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu 610059,China;State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil&Water Pollution,Chengdu University of Technology,Chengdu 610059,China;State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Environmental Sciences,Beijing 100012,China)

机构地区：[1]State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu 610059,China [2]State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil&Water Pollution,Chengdu University of Technology,Chengdu 610059,China [3]State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Environmental Sciences,Beijing 100012,China

出　　处：《Journal of Central South University》2024年第4期1217-1232,共16页中南大学学报（英文版）

基　　金：Projects(42077185,U22A20591);supported by the National Natural Science Foundation of China;Projects(2022JDJQ0010,2022ZYD0040);supported by the Sichuan Science and Technology Program for Distinguished Young Scholars,China;Project(2020YFC1808300);supported by the National Key Research and Development Program of China;Project(SKLGP2020Z002);supported by the Research Fund of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,China。

摘　　要：土壤中铬(Cr)污染是最严重的环境问题之一,对人类健康构成了重大威胁。本研究探讨了多硫化物修饰的nZVI@BC(PS-nZVI@BC)对铬污染土壤的稳定化机制以及铬的生物可用性。经过30天的处理后,添加PS-nZVI@BC能够降低土壤中92.0%的可浸出Cr(VI)。根据序贯萃取分析,添加PS-nZVI@BC后,土壤中的可交换铬从20.8%急剧下降至4.0%,大部分转化为铁锰氧化物和有机物结合态。稳定机制包括静电吸附、氧化还原反应、表面络合和沉淀。此外,PS-nZVI@BC能有效改善铬污染土壤的肥力,降低土壤中的铬对玉米幼苗的毒性。这些结果表明采用PS-nZVI@BC对受铬污染的土壤进行修复具有巨大的潜力。Chromium(Cr)contamination in soil is one of the most severe environmental issues,which poses significant health hazards to humans.In this study,the stabilization mechanism of Cr-contaminated soil by polysulfide-supported nZVI@biochar(PS-nZVI@BC)and the resultant bioavailability of Cr was studied.The addition of PS-nZVI@BC is capable of decreasing 92.0%of leachable Cr(VI)in the soil after 30 days of treatment.According to sequential extraction analysis,the exchangeable Cr in soil decreased drastically from 20.8%to 4.0%after PS-nZVI@BC addition,which was mostly converted to Fe-Mn oxided and organic matter-bound forms.The stabilization mechanisms include electrostatic adsorption,redox reaction,surface complexation,and precipitation.The soil fertility of Cr-contaminated soil was effectively improved by PS-nZVI@BC,and the toxicity of Cr in soil to maize seedlings was reduced.These results demonstrated the great potential of utilizing PS-nZVI@BC for the remediation of Cr-contaminated soils.

关 键 词：铬污染土壤 生物炭 多硫化物修饰nZVI 土壤修复 土壤肥力 

分 类 号：S15[农业科学—土壤学]