铁基复合材料对土壤Cd-As的同步稳定化  

Simultaneous stabilization of soil Cd-As by iron-based composites

作　　者：阎秀铭 罗家仪 刘千钧[1] 陈志良 肖荣波[1] YAN Xiuming;LUO Jiayi;LIU Qianjun;CHEN Zhiliang;XIAO Rongbo(School of Environmental Science and Engineering,Guangdong University of Technology,Guangzhou 510006;South China Institute of Environmental Sciences,Ministry of Ecology and Environment,Guangzhou 510535)

机构地区：[1]广东工业大学环境科学与工程学院,广州510006 [2]生态环境部华南环境科学研究所,广州510535

出　　处：《环境科学学报》2023年第7期339-347,共9页Acta Scientiae Circumstantiae

基　　金：广东省国际合作项目(No.2021A0505030045);广东省重点研发专项项目(No.2019B110207001)。

摘　　要：由于土壤中Cd和As的赋存形态、地球化学行为差异很大,在稳定化修复过程中其有效态含量随土壤各类指标的改变常呈此消彼长式变化.为达到使其同步稳定的目的,本文考察了以铁氧化物、木质素和高岭土为主要成分的复合材料(GLK)对土壤中的Cd、As的赋存形态、土壤理化性质以及铁形态分布的影响.结果表明:投加GLK可提高土壤的pH缓冲能力,增加土壤有机质含量、阳离子交换量、无定形铁氧化物和游离铁氧化物的含量,当投加量为5%(质量比)时,土壤Cd和As的有效态含量分别下降48.11%和33.58%.GLK可通过吸附、络合和表面沉淀等机制实现Cd、As的同步稳定化.Due to the highly variable distribution and geochemical behavior of Cd and As in soils,the bioavailability varies one another in response to soil indicators during stabilization.The effect of a composite material(GLK),which mainly contains iron oxides,lignin and kaolin,on the speciation distribution of Cd and As in the soil was investigated,as while as physicochemical properties,and the distribution of iron forms in soil.The pH buffering capacity of the soil could be improved after GLK application.The content of soil organic matter,cation exchange,amorphous iron oxides,and free iron oxides were increased after the application of GLK.The bioavailable Cd and As were decreased by 48.11%and 33.58%respectively under 5%(mass ratio)dosage of GLK.The simultaneous stabilization of Cd and As might be achieved with mechanisms such as adsorption,complexation,and surface precipitation.

关 键 词：镉 砷 铁氧化物 复合材料 稳定化 

分 类 号：X53[环境科学与工程—环境工程]