摘要
利用坡缕石(RPAL)并采用共沉淀法制备了MgO/PAL复合材料,该材料活化过一硫酸盐(PMS)可对草甘膦和镉(Cd)共污染的土壤进行有效修复.考察了不同镁盐剂量对MgO/PAL复合材料吸附Cd性能的影响,揭示了MgO/PAL复合材料结构形貌与吸附性能之间的构效关系.结果表明:当镁盐剂量为30 mL时,MgO在RPAL纳米棒表面均匀分布,比表面积为28.838 m^2·g^-1,MgO/PAL对Cd2+的吸附量为187.05 mg·g^-1.Zeta结果表明,随着镁盐剂量的增加,坡缕石表面由负电势向正电势转变,原位生成Cd(OH)2沉淀是MgO/PAL复合材料钝化Cd的主要机制.经MgO/PAL和PMS处理后,初始质量分数为10 mg·kg^-1 Cd污染土壤中Cd的浸出质量分数为0.93 mg·kg^-1,达到TCLP国际标准,草甘膦的去除率为73.81%.
The MgO/PAL composite material was prepared by co-precipitation method using palygorskite(RPAL),which can activate persulfate(PMS)to jointly repair glyphosate and cadmium(Cd)contaminated soil.The effects of different magnesium salt dosages on the Cd adsorption performance of MgO/PAL composites were studied,and the structure-effect mechanism relationship between morphology structure and adsorption performance of MgO/PAL composites was revealed.The experimental results suggest that when the magnesium salt was 30 mL,the adsorption capacity of MgO/PAL for Cd2+was 187.05 mg·g^-1.MgO was evenly distributed on the surface of RPAL Nanorods with the specific surface area of 28.838 m^2·g^-1.With the increase of the amount of magnesium salt,the surface of the attapulgite changed from negative potential to positive potential,thus the in situ Cd(OH)2 precipitation was the critical mechanism of passivation of Cd on the surface of MgO/PAL composite materials.After the 10 mg·kg^-1 Cd contaminated soil was treated by MgO/PAL+PMS,the leaching concentration of Cd was 0.93 mg·kg^-1,which reached the TCLP international standard and the removal rate of glyphosate was 73.81%.
作者
薛花
梁奔强
刘克斌
崔家浩
赵丹
傅剑锋
丁辉
XUE Hua;LIANG Benqiang;LIU Kebin;CUI Jiahao;ZHAO Dan;FU Jianfeng;DING Hui(School of Chemical Engineering,Tianjin University,Tianjin 300072,China;School of Environmental Science and Engineering,Tianjin University,Tianjin 300072,China;Tianjin Water Engineering Co.,Ltd,Tianjin 300222,China;Party School of CPC Shenyang Municipal Committee,Shenyang,110036,China)
出处
《沈阳大学学报(自然科学版)》
CAS
2020年第6期471-477,共7页
Journal of Shenyang University:Natural Science
基金
天津市科技计划项目(17YFNZNC00060)
天津市武清区科技发展计划项目(WQKJ201725).
关键词
草甘膦
镉
坡缕石
复合污染
农田土壤
化学氧化
glyphosate
cadmium
palygorskite
co-contamination,farmland soil,chemical oxidation
作者简介
薛花(1994-),女,安徽合肥人,硕士研究生;刘克斌(1967-),男,辽宁铁岭人,教授;通讯作者:丁辉(1976-),男,辽宁抚顺人,副教授,博士,E-mail:dinghui@tju.edu.cn。