碳纳米管/壳聚糖自组装离子印迹材料的制备及性能

Preparation and Properties of Multi-walled Carbon Nanotubes and Chitosan Self-assembled Ion Imprinted Polymers

以多壁碳纳米管(MWCNTs)为基质、壳聚糖(CS)为功能单体、Ni(Ⅱ)离子为模板、戊二醛为交联剂,采用静电自组装法制备了镍离子印迹材料MIIPs。采用SEM、XRD、FTIR及TG对其结构和性能进行了表征,采用丁二酮肟可见分光光度法对印迹聚合物的吸附性能进行了考察。结果表明;壳聚糖成功地接枝到碳纳米管表面,并且印迹材料对Ni(Ⅱ)具有选择吸附性能,化学吸附过程符合准二级吸附动力学模型,平衡吸附量为32.20mg/g,竞争离子Pb(Ⅱ)和Cu(Ⅱ)存在时,Ni(Ⅱ)/Pb(Ⅱ)和Ni(Ⅱ)/Cu(Ⅱ)的选择系数分别为11.27和9.22。

A novel kind of Ni^（2＋） ion imprinted polymers（MIIPs） based on multi-walled carbon nanotubes（MWCNTs） was synthesized via electrostatic self-assembly method using chitosan（CS） as functional monomer,Ni^（2＋） as template molecule and glutaraldehyde as cross-linker.The as-prepared MIIPs were characterized by means of scanning electron microscope（SEM）,X-ray diffraction（XRD）,Fourier transform infrared spectroscopy（FTIR） and thermogravimetry（TG）.The adsorption properties of ion imprinted polymers were investigated by dimethylglyoxime visible spectrophotometry.The studies indicated that chitosan was well grafted on the surface of MWCNTs,and the MIIPs displayed excellent adsorption and selectivity toward Ni^（2＋） .The adsorption processes obeyed pseudo second-order kinetic isotherms with a maximum capacity of 32.20 mg/g,and the selective coefficients were 11.27 and 9.22 confronting with common coexisting ions such as Pb^（2＋） and Cu^（2＋） ,respectively.