配体辅助Ni(Ⅱ)离子印迹材料的制备及性能

Preparation and performance of ligand⁃assisted Ni(Ⅱ)ion⁃imprinted materials

采用沉淀聚合法,以Ni(Ⅱ)离子为模板离子,邻氨基吡啶为配体,丙烯酰胺为功能单体,系统优化印迹条件,制备一系列Ni(Ⅱ)离子印迹聚合物Ni(Ⅱ)-IIP_(1-20)及相应的非印迹聚合物Ni(Ⅱ)-NIP_(1-20)。采用SEM(扫描电镜)、FT-IR(红外光谱)等对较优条件下制备的Ni(Ⅱ)-IIP_(3)及Ni(Ⅱ)-NIP_3进行结构表征,通过动力学吸附实验和等温吸附实验等进一步探究其吸附行为。结果表明:Ni(Ⅱ)-IIP_3对Ni(Ⅱ)离子的平衡吸附量达109.48 mg/g,印迹因子为3.70,是典型的介孔材料。其表面存在吸附Ni(Ⅱ)离子的特异性印迹孔穴,吸附行为更符合准二级动力学模型和Freundlich等温吸附模型。此外,在“竞争离子”Co(Ⅱ)离子存在的条件下,Ni(Ⅱ)-IIP_3对Ni(Ⅱ)离子仍具有较强的吸附能力和良好的吸附选择性,是一种性能优异的新型吸附材料。

A series of Ni(Ⅱ)ion⁃imprinted polymers Ni(Ⅱ)⁃IIP_(1⁃20) and corresponding non⁃imprinted polymers Ni(Ⅱ)⁃NIP_(1⁃20) were prepared by precipitation polymerization method using Ni(Ⅱ)ion as template ion,o⁃aminopyridine as ligand,acrylamide as functional monomer,and the systematic optimization of imprinting conditions.The SEM(scanning electron microscopy)and FT⁃IR(fourier transform infrared)were used to structurally characterize Ni(Ⅱ)⁃IIP_(3) and Ni(Ⅱ)⁃NIP_(3) prepared under the preferred conditions,and their adsorption behaviors were further explored by kinetic adsorption experiments and isothermal adsorption experiments.The results show that the equilibrium adsorption of Ni(Ⅱ)⁃IIP_(3) on Ni(Ⅱ)ions reaches 109.48 mg/g with an imprinting factor of 3.70,which is a typical mesoporous material.The specific imprinted pores for adsorption of Ni(Ⅱ)ions exist on its surface,and the adsorption behavior is more in line with the quasi⁃secondary kinetic model and the Freundlich isothermal adsorption model.In addition,in the presence of"competing ions"Co(Ⅱ)ions,Ni(Ⅱ)⁃IIP_(3) still has strong adsorption capacity and good adsorption selectivity for Ni(Ⅱ)ions,which is a new type of adsorbent material with excellent performance.