双重印迹法制备汞离子印迹聚合物及其性能研究

Synthesis and Properties Study of Mercury Ion Imprinted Polymer

采用双重印迹法,以N-3-(三甲氧基硅基)丙基乙二胺为功能单体,四乙氧基硅烷为交联剂,表面活性剂(十六烷基三甲基溴化铵)和Hg2+为模板,合成出Hg2+印迹聚合物。聚合物中的表面活性剂和Hg2+分别由乙醇萃取和HCl洗涤除去,利用平衡吸附法研究了聚合物的吸附性能和选择识别能力,且探讨了实验条件对印迹聚合物吸附性能的影响。结果表明,在竞争离子Cu2+(或Cd2+)存在下,印迹聚合物具有较高的吸附能力和选择识别能力,最大相对选择系数k′>200,且可以循环使用。

A new type of Hg^2＋ imprinted polymer was prepared by a double-imprinting approach for the selective separation of Hg^2＋ from aqueous solution. In the imprinting process, both mercury ions and surfactant micelles （ cetyltrimethylammonium bromide） were used as templates, N- [ 3- （trimethoxy-silyl） propyl ] ethylenedi- amine as functional monomer, and tetraethoxysilane as cross-linking agent. The mercury ions and surfactant were removed from polymer via acid leaching and ethanol extraction, respectively. The adsorption property and selective recognition ability of the polymer were studied by equilibrium-adsorption method. Results showed that in the presence of Cu^2＋ or Cd^2＋ , the largest relative selectivity coefficient （k′） of the ion-imprinted polymer was over 200, and the polymer could be used repeatedly.