铅离子印迹聚合物的制备及吸附性能研究

Preparation of lead ion-imprinted polymer and its adsorption properties

以磁性碳纳米管(Fe_(3)O_(4)/MWCNTs-COOH)为基质,壳聚糖(CS)、甲基丙烯酸甲酯(MMA)为功能单体,戊二醛为交联剂,Pb^(2+)为模板,采用反相悬浮聚合法制得一种新型铅离子印迹材料(IIPs)。利用FT-IR、XRD、TG、SEM对其进行结构表征,通过UV-Vis和AAS研究了IIPs的吸附特性。结果表明,IIPs对Pb^(2+)平衡吸附量为33.60 mg/g,该吸附过程符合准二级动力学模型,在竞争离子Cu^(2+)和Cd^(2+)存在时,Pb^(2+)/Cu^(2+)和Pb^(2+)/Cd^(2+)的选择系数分别为7.62和6.04。

A novel kind of lead ion-imprinted polymers(IIPs),based on magnetic carbon nanotubes(Fe_(3)O_(4)/MWCNTs-COOH),is prepared by reverse suspension polymerization with using chitosan(CS),methyl methacrylate(MMA)as monomers,glutaraldehyde as crosslinking agent and Pb^(2+) as template.IIPs are characterized by Fourier transform infrared spectrometer(FT-IR),X-ray diffraction(XRD),thermogravimetric Analysis(TG),and scanning Electron Microscope(SEM).Adsorption characteristics of IIPs are evaluated by ultraviolet spectrophotometer(UV-Vis)and atomic absorption spectrophotometer(AAS).Results indicate that the equilibrium adsorption capacity of IIPs to Pb^(2+) is 33.60 mg·g^(-1).The adsorption process conforms to a pseudo-second-order kinetic model.In the presence of competitive ions including Cu^(2+) and Cd^(2+),the selection coefficients of Pb^(2+)/Cu^(2+) and Pb^(2+)/Cd^(2+) are 7.62 and 6.04,respectively.