海泡石改性纳米零价铁对Cd的吸附效果及其机制  

Adsorption effect of Cd(Ⅱ)by sepiolite-modified nanoscale zero-valent iron and mechanistic study

作　　者：梅哈古丽·艾尼瓦尔 张拓 殷宪强[3] 张楠 彭礼枚 李洪斌 曾希柏[1] MEIHAGULI Ainiwaer;ZHANG Tuo;YIN Xianqiang;ZHANG Nan;PENG Limei;LI Hongbin;ZENG Xibai(Institute of Environment and Sustainable Development in Agriculture,Chinese Academy of Agriculture Sciences,Beijing,100081,China;College of Resources and Environment,Xinjiang Agricultural University,Urumqi,830052,China;College of Natural Resources and Environment,Northwest A&F University,Yangling,712100,China;School of Environmental and life Science,Nanning Normal University,Nanning,530001,China;Hunan GRG Metrology&Test Limited Company,Changsha,410017,China)

机构地区：[1]中国农业科学院农业环境与可持续发展研究所,北京100081 [2]新疆农业大学资源与环境学院,新疆维吾尔自治区,乌鲁木齐830052 [3]西北农林科技大学资源环境学院,杨凌712100 [4]南宁师范大学环境与生命科学学院,南宁530001 [5]广电计量检测(湖南)有限公司,长沙410017

出　　处：《环境化学》2025年第1期322-333,共12页Environmental Chemistry

基　　金：国家重点研发计划(2022YFD1700102,2022YFD1700105);国家自然科学基金(U19A2048);四川省自然科学基金(2022NSFSC1059);中国农业科学院科技创新工程项目(CAAS-AST2P-2021-2EDA)资助.

摘　　要：为明确海泡石改性纳米零价铁(S-nZVI)对Cd在水体和土壤中的吸附效果及其作用机制,本研究采用批量吸附和土培试验,结合现代光谱表征分析等方法,探究了S-nZVI对Cd的吸附及影响因素,并深入分析了S-nZVI对镉吸附的吸附作用机制.结果表明,负载nZVI提高了海泡石对Cd的吸附能力,S-nZVI对Cd的饱和吸附量达到11.37 mg·g^(−1);S-nZVI对Cd的等温吸附更符合Freundlich模型,该过程属于多层吸附;S-nZVI对Cd(Ⅱ)的吸附量随pH的增加而显著增加,磷酸根和硝酸根离子的存在能促进S-nZVI对Cd的吸附.不同S-nZVI的添加剂量均能显著降低土壤有效镉的含量,其中5%W/W的添加量表现效果最好.综合批量吸附实验和光谱分析(XPS和XRD)的结果发现S-nZVI对Cd的吸附作用机制主要包括离子交换、静电吸附、沉淀和络合作用.本研究的结果证明了S-nZVI可以作为一种对镉具有良好吸附作用的材料,并且在镉中轻度污染水体和土壤修复中具有较广泛的应用前景.In order to investigate the adsorption effect of nano zero-valent iron modified by sepiolite(S-nZVI)on Cd in water and soil and its mechanism,this work used batch adsorption experiment and soil incubation experiment,combined with modern spectral characterization analysis methods,to explore the adsorption of S-nZVI on Cd,influencing factors and deeply analyze the adsorption mechanism of S-nZVI on cadmium.The results showed that nZVI loading improved the adsorption capacity of sepiolite for Cd(Ⅱ),and the adsorption capacity of S-nZVI for Cd(Ⅱ)was 11.37 mg·g^(−1),The isotherm adsorption of Cd(Ⅱ)by S-nZVI was better fitted with the Freundlich model,which belongs to multi-layer adsorption.The adsorption adsorption capacity increased with pH increment,and PO_(4)^(3−)and NO_(3)^(−)promoted the removal of Cd(Ⅱ).Different dosage of S-nZVI can significantly reduce the content of available cadmium in soil,and the addition of 5%W/W has the best effect.The results of batch adsorption test and spectral analysis(XPS and XRD)found that ions exchange,electric attraction,precipitation and surface complexation were the main mechanisms for Cd(Ⅱ)to removal Cd.In conclusion,S-nZVI can be used as a stabilizing material for Cd remediation in mild and moderately polluted water and soil.

关 键 词：海泡石 纳米零价铁 镉 吸附机制 

分 类 号：X-1[环境科学与工程] O6[理学—化学]