生物炭/凹凸棒石复合材料对土壤中Cd的钝化效果研究  

Study on the Passivation Effect of Biochar/attapulgite Composite Material on Cd in Soil

作　　者：马贵[1,2,4] 任珺 陶玲[1,2,3] 吕麦蓉 周悦[4] 廖彩云 丁家富 毕可心 MA Gui;REN Jun;TAO Ling;L Mairong;ZHOU Yue;LIAO Caiyun;DING Jiafu;BI Kexin(Key Laboratory of Yellow River Water Environment in Gansu Province,Lanzhou Jiaotong University,Lanzhou 730070,China;School of Environmental and Municipal Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;Gansu Hanxing Environmental Protection Co.Ltd.,Lanzhou 730070,China;College of Chemistry and Chemical Engineering,Ningxia Normal University,Guyuan 756000,Ningxia,China)

机构地区：[1]兰州交通大学甘肃省黄河水环境重点实验室,兰州730070 [2]兰州交通大学环境与市政工程学院,兰州730070 [3]甘肃瀚兴环保科技有限公司,兰州730070 [4]宁夏师范学院化学与化工学院,宁夏固原756000

出　　处：《兰州交通大学学报》2023年第5期98-103,共6页Journal of Lanzhou Jiaotong University

基　　金：甘肃省教育厅产业支撑计划项目(2021CYZC-31);甘肃省科技厅科技计划项目(22CX3GA076);兰州市人才创新创业项目(2021-RC-41);宁夏自然科学基金项目(2023AAC03336);甘肃省优秀研究生“创新之星”项目(2022CXZX-514)。

摘　　要：通过一步水热法将马铃薯秸秆与凹凸棒石制备成水热炭/凹凸棒石复合材料(BATP)用于Cd污染土壤的钝化修复,用扫描电镜和傅立叶红外光谱对其进行表征,通过钝化和盆栽试验探究其对土壤中Cd的钝化效果。结果表明:碱性水热条件下,秸秆的碳化促进了凹凸棒石及伴生矿物的分散,使片状或颗粒状矿物分布在水热炭表面。添加BATP后,土壤pH、阳离子交换量和电导率均明显升高;与CK相比,二乙烯三胺五乙酸(DTPA)提取态Cd和毒性特征浸出(TCLP)Cd分别较CK降低6.02%~19.12%和8.56%~27.34%,酸溶态Cd的质量分数降低2.41%~9.51%,残渣态Cd的质量分数增加8.37%~27.78%。此外,添加BATP能促进玉米幼苗的生长,减少玉米幼苗根和茎中Cd含量,且当添加量为5%时,玉米根和茎的鲜重、干重及长度增幅均达到最大,玉米地上和地下部分Cd质量分数分别降低25.82%和11.5%。可见,BATP可用于Cd污染土壤的钝化修复。A hydrothermal biochar/attapulgite composite(BATP)was prepared from potato straw and graptolite by one-step hydrothermal method and used for the passivation remediation of Cd-contaminated soil,which was characterized by scanning electron microscopy(SEM)and Fourier infrared spectroscopy(FT-IR).The results showed that the carbonization of straw under alkaline hydrothermal conditions promoted the dispersion of attapulgite and associated minerals,and resulted in the distribution of flake or granular minerals on the biochar surface.The addition of BATP significantly increased soil pH,cation exchange,and conductivity;diethyl enetriamin epentaacetic acid extracted(DTPA)Cd while toxic characteristic leaching(TCLP)Cd were reduced by 6.02%~19.12%and 8.56%~27.34%,respectively,compared with CK;the addition of BATP reduced the acid soluble speciation Cd content by 6.02%~19.12%while the residual speciation Cd was increased by 8.56%~27.34%,compared with CK.In addition,the addition of the BATP promoted the growth of maize seedlings and reduced the Cd content of roots and stems of maize seedlings,and the increase of root fresh weight,stem fresh weight,root dry weight,stem dry weight,stem length and root length of maize reached the maximum when the addition amount was 5%,and the Cd content of above and below ground parts of maize was decreased by 25.82%and 11.5%,respectively.In brief,BATP can be used for the passivation remediation of Cd-contaminated soils.

关 键 词：水热 生物炭 凹凸棒石 CD 钝化 

分 类 号：X53[环境科学与工程—环境工程]