MgAl-LDHs磁性颗粒对镉污染农田土壤的减量修复研究  

Reduced Remediation of Cadmium Contaminated Farmland Soil by Mg-Al-Layered Double Hydroxide Magnetic Particles

作　　者：王启豪 刘国明 涂晨[2] 李远[3] 王译 李忠元 骆润来 陈星 潘响亮 骆永明[2] WANG Qihao;LIU Guoming;TU Chen;LI Yuan;WANG Yi;LI Zhongyuan;LUO Runlai;CHEN Xing;PAN Xiangliang;LUO Yongming(Institute of Environmental Ecology and Engineering,Faculty of Environment,Zhejiang University of Technology,Hangzhou 310014,China;CAS Key Laboratory of Soil Environment and Pollution Remediation,Institute of Soil Science,Chinese Academy of Sciences,Nanjing 210008,China;CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation,Yantai Institute of Coastal Zone Research,Chinese Academy of Sciences,Yantai,Shandong 264003,China;CSCEC Eco-Environmental Engineering Research Center(Soil Remediation Technology and Equipment),China Construction Eighth Engineering Division Co.,Ltd.,Shanghai 200444,China)

机构地区：[1]浙江工业大学环境学院环境生态与工程研究所,杭州310014 [2]中国科学院土壤环境与污染修复重点实验室(南京土壤研究所),南京210008 [3]中国科学院海岸带环境过程与生态修复重点实验室(烟台海岸带研究所),山东烟台264003 [4]中国建筑生态环境工程研究中心(土壤修复技术与装备),中国建筑第八工程局有限公司,上海200444

出　　处：《土壤》2023年第6期1297-1305,共9页Soils

基　　金：国家重点研发计划项目(2022YFD1700104);国家自然科学基金重大项目(41991330);中国建筑生态环保工程研究中心(土壤修复技术与装备),中国建筑第八工程局有限公司项目(CSCEC-PT-009)资助。

摘　　要：以不同巯基改性的镁铝层状双金属氢氧化物(MgAl-LDHs)为原材料制备了4种毫米级磁性颗粒修复材料,并开展了对土壤中镉(Cd)去除效果的对比试验,考察了MgAl-LDHs磁性颗粒修复材料的投加量和作用时间对Cd去除效果的影响,探讨了修复材料对3种实际污染农田土壤(Cd总量在0.73~0.86mg/kg)中Cd的去除效果与机制。结果表明:以泰克莱尔MgAl-LDHs为原材料制得的磁粒MgAl-LDHs-C对Cd的去除效果最好,其与土壤的最佳投加质量比为1∶10,最适作用时间为3 h,在此条件下,浙江台州土壤DTPA提取态Cd含量由0.56mg/kg下降至0.30mg/kg;控制m土∶V液为1∶2,反应温度为25℃,振荡频率为180r/min,按照最优选投加量和作用时间分别向江苏太仓、甘肃白银和浙江台州污染农田土壤中施用MgAl-LDHs-C,3种土壤中Cd总量去除率分别达到26.0%、23.8%和34.7%。土壤Cd形态分析结果显示,MgAl-LDHs-C可以显著降低土壤可交换态、可还原态、可氧化态Cd的含量。因此,本研究所制备的MgAl-LDHs-C材料具有良好的土壤Cd去除能力,可为Cd污染农田土壤的减量修复提供科学依据。In this study,millimeter scale magnetic particle materials were prepared by using thiol-functionalized MgAl-LDHs from four different sources,respectively,their impacts of dosage and treatment time on the effect of Cd removal were examined,and then the removal effect and mechanism of MgAl-LDHs-C on the removal of Cd in three actual contaminated agricultural soils(total Cd 0.73–0.86 mg/kg)were investigated.The results showed that MgAl-LDHs-C magnetic particle made from Tech-layer MgAl-LDHs had the best removal effect.The optimum mass ratio of MgAl-LDHs-C to soil was determined to be 1∶10,and the optimal reaction time was 3 h.Under this condition,the DTPA extracted Cd content in soil from Taizhou City of Zhejiang Province decreased from 0.56 mg/kg to 0.30 mg/kg.Under optimum conditions of liquid-solid ratio 2∶1,reaction temperature 25°C,oscillation frequency 180 r/min,the total Cd removal rates of the soils collected from Taicang City of Jiangsu Province,Baiyin City of Gansu Province and Taizhou City of Zhejiang Province were 26.0%,23.8%and 34.7%,respectively.In conclusion,MgAl-LDHs-C addition can significantly lower soil acid-soluble,reduced and oxidized Cd contents,and the MgAl-LDHs-C material prepared in this study demonstrates strong soil Cd removal ability,which can provide a scientific basis for the reduction remediation of Cd-contaminated farmland soil.

关 键 词：CD 污染农田土壤 减量修复 MgAl-LDHs 磁性材料 

分 类 号：X53[环境科学与工程—环境工程]