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以正硅酸乙酯和2-氰乙基三乙氧基硅烷为硅源,聚(乙二醇)-聚(丙二醇)-聚(乙二醇)三嵌段共聚物为模板剂,采用共缩聚法水热合成了氰基介孔二氧化硅(CN-SBA-15),然后与羟胺发生胺肟化反应将氰基功能化二氧化硅转化为偕胺肟基介孔二氧化硅(AO-SBA-15).用傅里叶红外光谱仪、N2吸附-脱附对其结构进行了表征,并以AO-SBA-15作为吸附剂,研究吸附过程的动力学和等温特性.表征结果表明,孔径为4.76 nm,且存在较大比例的微孔,有利于络合铜离子.吸附动力学和等温线拟合结果表明,吸附过程较符合拟二级动力学模型;Langmuir模型能很好地描述AO-SBA-15对水中Cu2+的实际的吸附情况,且在40℃时最大吸附量为34.18 mg/g.热力学研究表明,吸附过程是一个吸热的自发过程,且高温更有利于吸附反应.“,”Amidoxime-functionalized mesoporous silica was synthesized by co-condensation of tetraethylorthosilicate and 2-cyanoethyl triethoxysilane as silicon source,poly (ethylene glycol)-poly (propylane glycol)-poly (ethylene glycol) three block copolymers as template.Hydroxylamine was used in the conversion of cyano group to amidoxime group by amidoximation reaction in aqueous solution.The synthesized mesoporous samples were characterized by Fourier-transform infrared spectroscopy and N2 adsorption-desorption.The samples were also used as sorbents to study adsorption kinetics and adsorption isotherms.The results showed that the pore size of sample was 4.76 nm with a big proportion ofmicroporous pore,which was propitious to complex copper ions.Adsorption kinetics and isotherm fitting results indicated that the pseudo-second-order kinetic model was found to be suited well for the entire adsorption process.Adsorption equilibrium data could be described well by Langrnuir model and the maximum adsorption capacity ofCu2+ was 34.18 mg/g at 40 ℃.Thermodynamics results showed that the adsorption process was a spontaneous and endothermic process and higher temperature was more conducive to the adsorption reaction.