title: Stabilisation of nanoscale zero-valent iron with biochar for enhanced transport and in-situ remediation of hexavalent chromium in soil.
abstract: In this study, a biochar-supported nanoscale zero-valent iron (nZVI@BC) material was used for in situ remediation of hexavalent chromium-contaminated soil. Sedimentation tests and column experiments were used to compare the stability and mobility of nZVI@BC and bare-nZVI. The immobilisation efficiency of chromium, toxic effect of chromium and the content of iron were assessed through leaching tests and pot experiments. Sedimentation tests and transport experiments indicated that nZVI@BC with nZVI to BC mass ratio of 1:1 exhibited better stability and mobility than that of bare-nZVI. The immobilisation efficiency of Cr(VI) and Crtotal was 100% and 92.9%, respectively, when the soil was treated with 8 g/kg of nZVI@BC for 15 days. Moreover, such remediation effectively reduced the leachability of Fe caused by bare-nZVI. In addition, pot experiments showed that such remediation reduced the phytotoxicity of Cr and the leachable Fe and was favourable for plant growth.
authors.affiliation: School of Chemistry and Environment, South China Normal University, Guangzhou, Guangdong 510006, China; Guangdong Technology Research Center for Ecological Management and Remediation of Water System, Guangzhou, Guangdong 510006, China.
authors.forename: Huijie
authors.initials: H
authors.lastname: Su
authors.affiliation: School of Chemistry and Environment, South China Normal University, Guangzhou, Guangdong 510006, China; Guangdong Technology Research Center for Ecological Management and Remediation of Water System, Guangzhou, Guangdong 510006, China. Electronic address: sunmoon124@163.com.
authors.forename: Zhanqiang
authors.initials: Z
authors.lastname: Fang
authors.affiliation: Guangdong Technology Research Center for Ecological Management and Remediation of Water System, Guangzhou, Guangdong 510006, China; Department of Science and Environmental Studies, Hong Kong Institute of Education, 00852, Hong Kong, China.
authors.forename: Pokeung Eric
authors.initials: PE
authors.lastname: Tsang
authors.affiliation: School of Chemistry and Environment, South China Normal University, Guangzhou, Guangdong 510006, China; Guangdong Technology Research Center for Ecological Management and Remediation of Water System, Guangzhou, Guangdong 510006, China.
authors.forename: Jianzhang
authors.initials: J
authors.lastname: Fang
authors.affiliation: Environmental Engineering Program, Department of Civil Engineering, Auburn University, Auburn, AL 36849, USA.
authors.forename: Dongye
authors.initials: D
authors.lastname: Zhao
mesh_terms: D002606:Charcoal / Q000737:chemistry*; D002857:Chromium / Q000737:chemistry*; D004787:Environmental Pollution / Q000032:analysis; D052918:Environmental Restoration and Remediation; D007501:Iron / Q000737:chemistry*; D063245:Plant Development; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry*
chemical_list: D012987:Soil; D012989:Soil Pollutants; C540010:biochar; D002857:Chromium; D002606:Charcoal; C074702:chromium hexavalent ion; D007501:Iron
keywords: Cr(VI)-contaminated soil; Mobility; Phytotoxicity; Stability; nZVI@BC