β-环糊精功能化生物炭对重金属复合污染土壤的修复研究

Study on the remediation of heavy metals contaminated soil byβ-cyclodextrin functionalized biochar

为探究β-环糊精功能化生物炭对重金属复合污染土壤的修复,采用微波辅助一锅法快速制备乙二胺四乙酸交联β-环糊精改性生物炭(BC-CD_(MW))并应用于土壤Pb和Cd的修复。BC-CD_(MW)吸附试验结果表明,对Pb^(2+)和Cd^(2+)的吸附在60和80 min时可达到平衡且最大吸附量分别为168.37和18.48 mg·g^(-1)。土壤修复试验结果表明,与CK和BC相比,添加BC-CD_(MW)可有效促使Pb和Cd的不稳定形态向残渣态转化21.53%和30.54%,降低其迁移和生物可利用性。通过土壤理化性质分析,BC-CD_(MW)的投加未对土壤造成危害,补充土壤中有机碳含量。可见,BC-CD_(MW)可作为土壤Pb和Cd修复的有效材料。

Ethylenediaminetetraacetic acid crosslinkedβ-cyclodextrin modified biochar(BC-CD_(MW))was fast prepared by microwave-assisted one-pot synthesis,and was applied to remediation of Cd and Pb contaminated soil.The results of BC-CD_(MW)adsorption experiments presented that the maximum adsorption capacities of Pb^(2+)and Cd^(2+)were 168.37 and 18.48 mg·g^(-1),respectively,with equilibrium times at 60 and 80 min.The results of soil remediation experiments showed that compared with CK and BC,the addition of BC-CD_(MW)effectively promoted the conversion of Pb and Cd from unstable form to residue state by 21.53%and 30.54%,respectively,and reduced their migration and bioavailability.Moreover,according to the analysis of soil physical and chemical properties,the addition of BC-CD_(MW)did not cause harm to soil and increased the organic carbon content in the soil.Therefore,BC-CD_(MW)could be used as an effective material for Pb and Cd remediation in soil.