聚合物改性膨润土对Pb(Ⅱ)离子的吸附特性研究  

Sorption properties of polymer-modified bentonite to Pb(Ⅱ)ions

作　　者：姜璐莎 蒲诃夫 闵明 邱金伟 陈晓雄 JIANG Lusha;PU Hefu;MIN Ming;QIU Jinwei;CHEN Xiaoxiong(School of Civil and Hydraulic Engineering,Huazhong University of Science and Technology,Wuhan 430074,China;College of Civil and Transportation Engineering,Shenzhen University,Shenzhen 518060,China;Key Laboratory of Geotechnical Mechanics&Engineering of Ministry of Water Resources,Yangtze River Scientific Research Institute,Wuhan 430010,China)

机构地区：[1]华中科技大学土木与水利工程学院,湖北武汉430074 [2]深圳大学土木与交通工程学院,深圳广东518060 [3]长江科学院水利部岩土力学与工程重点实验室,湖北武汉430010

出　　处：《岩土工程学报》2024年第S02期54-59,共6页Chinese Journal of Geotechnical Engineering

基　　金：国家重点研发计划项目(2019YFC1806000);国家自然科学基金项目(52078235,52208329)。

摘　　要：为研究聚合物改性膨润土(简称PMB)对重金属的吸附特性,开展了Batch吸附试验,利用4种吸附动力学模型(准一阶动力学、准二阶动力学、颗粒内扩散和Elovich模型)和4种等温吸附模型(Langmuir、Freundlich、D-R和Temkin模型)研究了钠化钙基膨润土(简称NCB)和PMB对Pb(Ⅱ)离子的吸附行为,并通过BET (Brunauer-Emmett-Teller)试验对膨润土进行了比表面积和孔径分析。结果表明,当溶液pH值为1 (强酸)时,PMB对Pb(Ⅱ)离子的吸附率为60%,较NCB提高了33%。膨润土对Pb(Ⅱ)离子的吸附动力学更符合准二阶模型,PMB在初始5 min内可快速吸附Pb(Ⅱ)离子,吸附率达50%。Langmuir吸附等温模型更好地描述了两种膨润土对Pb(Ⅱ)离子的吸附特性,计算所得最大吸附量与试验结果接近。To investigate the heavy metal sorption properties of the polymer-modified bentonite(PMB),the batch sorption tests are conducted.The sorption behaviors of the sodium activated calcium-bentonite(NCB)and PMB to Pb(Ⅱ)ions are investigated using four sorption kinetic models(i.e.,pseudo-first-order,pseudo-second-order,intra-particle diffusion,and Elovich models)and four isothermal sorption models(i.e.,Langmuir,Freundlich,D-R,and Temkin models).Additionally,the specific surface area and pore size distribution of the bentonites are analyzed the through BET(Brunauer-Emmett-Teller)tests.The results indicate that at solution pH=1(strong acidity),the sorption efficiency of the PMB to Pb(Ⅱ)ions is 60%,with an improvement of 33%over the NCB.The sorption kinetics of bentonites to Pb(Ⅱ)ions conformes more closely to the pseudo-second-order model,with the PMB rapidly adsorbing Pb(Ⅱ)ions within the first 5 minutes,achieving the sorption rate of 50%.The Langmuir sorption isotherm model provides a better description of the sorption characteristics of both bentonites to Pb(II)ions,and the calculated maximum sorption capacity closely matches the testing results.

关 键 词：膨润土 聚合物改性 吸附性能 铅离子 

分 类 号：TU443[建筑科学—岩土工程]