氨基改性埃洛石对Cu(II)和Cd(II)的吸附研究  

Preparation of Amino-modified Halloysite and Its Adsorption to Cu(Ⅱ)and Cd(Ⅱ)

作　　者：肖雪 于文彬[2] 谭道永 吴兴福 覃宗华[2] 万泉[2] XIAO Xue;YU Wenbin;TAN Daoyong;WU Xingfu;QIN Zonghua;WAN Quan(Key Laboratory of Solid Waste Treatment and Resource Recycle,Ministry of Education,Southwest University of Science and Technology,Mianyang Sichuan 621010,China;State Key Laboratory of Ore Deposit Geochemistry,Institute of Geochemistry Chinese Academy of Science,Guiyang Guizhou 550081,China;School of Chemistry and Materials Science,Guizhou Education University,Guiyang Guizhou 550018,China)

机构地区：[1]西南科技大学环境与资源学院,四川绵阳621010 [2]中国科学院地球化学研究所矿床地球化学国家重点实验室,贵州贵阳550081 [3]贵州师范学院化学与材料学院,贵州贵阳550018

出　　处：《矿物学报》2025年第1期169-180,共12页Acta Mineralogica Sinica

基　　金：贵州省科技计划项目(编号:黔科合基础-ZK[2021]重点043);贵州省优秀青年科技人才项目(编号:黔科合平台人才-YQK[2023]037)。

摘　　要：本研究采用3-氨丙基三乙氧基硅烷对管状埃洛石(Hal)进行共价接枝制备了氨基改性埃洛石(Hal-NH_(2)),通过XRD、TEM、SEM、氮气吸脱附等手段表征了Hal-NH_(2)的结构特征,并通过批次吸附实验、谱学技术研究了Hal-NH_(2)对Cu(II)和Cd(II)的吸附性能及机理。Hal-NH_(2)中氨基主要存在于Hal的内腔,其氨基嫁接量为0.83 mmol/L,由于硅烷嫁接占据了部分内腔孔道,Hal-NH_(2)的比表面积和总孔体积较Hal明显降低。Hal-NH_(2)对Cu^(2+)和Cd^(2+)的吸附随溶液初始p H值的增大而增加,吸附时间为2160 min时达到吸附平衡,298 K时,Hal-NH_(2)对Cu^(2+)和Cd^(2+)的Langmuir吸附量分别为50.29和68.70 mg/g,是Hal的3.11和1.97倍。Hal-NH_(2)吸附Cu^(2+)和Cd^(2+)为自发的吸热反应,吸附后体系的混乱度增大,其吸附机制主要是氨基与重金属离子之间发生配位反应,且Hal-NH_(2)对Cu^(2+)的作用力强于Cd^(2+);Cu^(2+)和Cd^(2+)共存时,Hal-NH_(2)对Cu^(2+)的吸附基本不受影响,其对Cd^(2+)的吸附显著降低。由于其较高的吸附能力,Hal-NH_(2)可作为Cu(II)和Cd(II)吸附材料用于水体中重金属离子的去除,本研究为Hal在重金属污染治理领域的应用提供了实验和理论依据。In this study,amino-modified halloysite(Hal-NH_(2))was prepared by using the covalent grafting of tubular halloysite(Hal)with(3-aminopropyl)triethoxysilane,the structural characteristics of the Hal-NH_(2) were characterized by using the XRD,TEM,SEM,and nitrogen adsorption–desorption techniques,and the adsorption performances and mechanisms of the Hal-NH_(2) on Cu(II)and Cd(II)were investigated through batch adsorption experiments and spectroscopic techniques.The amino groups in the Hal-NH_(2) mainly occurred in the lumen of the Hal,with the grafting amount of amino groups of 0.83 mmol/L.The specific surface area and total pore structure of the Hal-NH_(2) were significantly reduced comparing with that of the pristine Hal,because parts of the internal pore channels of the Hal-NH_(2) were occupied by the grafted silane.The adsorption capabilities of Cu^(2+)and Cd^(2+)by the Hal-NH_(2) are increased with the increase of initial pH values of the solutions,with the adsorption equilibrium reached at an adsorption time of 2160 min.The Langmuir adsorption capacities of Cu^(2+)and Cd^(2+)by the Hal-NH_(2) at 298 K were 50.29 mg/g and 68.70 mg/g,respectively,which are 3.11 and 1.97 times higher than those of halloysite,respectively.The adsorption of Cu^(2+)and Cd^(2+)by the Hal-NH_(2) is a spontaneous and endothermic process,resulting in the increased disorder of the system.The adsorption mechanism is mainly the coordination reaction between the amino groups and heavy metal ions,and the affinity between the Hal-NH_(2) and Cu^(2+)is stronger than that of the Hal-NH_(2) and Cd^(2+);When Cu^(2+)and Cd^(2+)are coexisted in the system,the adsorption capability of the Hal-NH_(2) on Cu^(2+)was unaffected,but the adsorption capability of the Hal-NH_(2) on Cd^(2+)was significantly reduced.Due to the high adsorption capacity,the Hal-NH_(2) can be used as Cu(II)and Cd(II)adsorption material for the removal of heavy metal ions from wastewater.This study provides an experimental and theoretical basis for the application of halloysite

关 键 词：埃洛石 氨基改性 吸附 重金属 CU(II) CD(II) 

分 类 号：P579[天文地球—矿物学]