新型汞离子印迹聚合物的吸附性能研究∗

摘要

A new Hg(Ⅱ)ion-imprinted polymer(Hg(Ⅱ)-IIP)microspheres was synthesised for the separation and recovery of Hg(Ⅱ)ion from water sample.Hg(Ⅱ)-IIP was prepared by copolymerisation of 2-allylsulfa-nyl-5-(4-pyridinyl)-[1,3,4]thiadiazole (AST),phenylethylene(St)and Hg(Ⅱ)ion.The structure and mor-phology of Hg(Ⅱ)-IIP and NIP were characterized by Fourier transform infrared spectroscopy(FT-IR)and scanning electronmicroscopy(SEM).The adsorptive properties and the selectivity recognition ability of Hg(Ⅱ)-IIP were investigated.The results indicated that the maximum adsorption capacity was 38.5 mg/g,the adsorp-tion capacity reached equilibrium need 30 min at pH 5-8.Using 0.1 mol/L HCl and 0.5 mol/L thiourea as de-sorption solvent,the desorption rate was more than 97%.The relatively selective factor (αr)values of Hg(Ⅱ)/Cd(Ⅱ),Hg(Ⅱ)/Co(Ⅱ),Hg(Ⅱ)/Ni(Ⅱ),Hg(Ⅱ)/Zn(Ⅱ)and Hg(Ⅱ)/Mn(Ⅱ)are 6.56,14.9,14.5,8.53 and 12.1,respectively.Hg(Ⅱ)-IIP had excellent adsorption and selective recognition properties.%以2-烯丙基硫代-5-(4-吡啶基)-[1,3,4]噻二唑(AST)、苯乙烯(St)为单体,Hg(Ⅱ)离子作为模板,制备了新型的汞离子印迹共聚物(Hg(Ⅱ)-IIP).采用傅里叶变换红外光谱仪(FT-IR)和扫描电镜(SEM)对印迹和非印迹聚合物的结构和形貌进行了表征.以原子吸收光谱法(FAAS)为检测手段,研究了 Hg(Ⅱ)-IIP 对 Hg (Ⅱ)离子的吸附和选择识别能力.结果表明,在 pH 值5~8条件下,30 min 即可达吸附平衡,饱和吸附量是38．5 mg/g.以0．1 mol/L HCl 与0．5 mol/L 硫脲水溶液作为洗脱剂,洗脱率达97％.Hg(Ⅱ)/Cd(Ⅱ),Hg (Ⅱ)/Co(Ⅱ),Hg(Ⅱ)/Ni(Ⅱ),Hg(Ⅱ)/Zn(Ⅱ)和 Hg(Ⅱ)/Mn(Ⅱ)的相对选择性系数分别为6．56,14．9,14．5,8．53和12．1,体现了 Hg(Ⅱ)-IIP良好的选择吸附和识别能力.