Cu(Ⅱ)-PEI螯合物电沉积制备离子印迹复合膜及其性能

Preparation of ion-imprinted membrane by Cu(Ⅱ)-PEI electro-deposition and it's performance

采用商品化的阳离子交换膜为基膜,以Cu2+作为模板离子,环氧氯丙烷为交联剂,通过电沉积法将螯合了铜模板离子的聚乙烯亚胺(Cu(Ⅱ)-PEI)沉积到基膜表面制备离子选择性复合膜.通过ATR-FTIR和扫描电子显微镜(SEM)对制备过程中膜表面特性及形貌进行了分析.以价态和离子半径都很接近的Zn2+作为竞争离子测定了复合膜对Cu2+的选择性,结果表明该方法制得的复合膜对Cu2+有特定的识别性能,在分离混合溶液过程中能够实现对Cu2+的优先透过.随着沉积溶液中Cu与N物质的量比的增大,制得的复合膜的选择性系数呈现先增大后变小的趋势,在Cu∶N为1∶8时制得的膜的选择性最优.

Abstract A novel ion-selective composite membrane was fabricated by electro-depositing compound polyethyleneimine chelated copper （Cu （Ⅱ） -PEI） on a commercialized cation-exchange membrane and subsequently modified with ion imprinting procedure. The Cu （Ⅱ ） -PEI modified membrane was then crosslinked with epichlorohydrin and the template Cu2＋ was leached with hydrochloric acid. Examination by infrared spectroscopy and scanning electron microscopy （SEM） confirmed PEI was successfully deposited onto the surface of cation-exchange membrane. Zn2＋ was selected as competitive ion due to similar charge and ionic radius. The result ofpermselective experiments showed that the prepared Cu2＋ imprinted membrane has the ability of specificity and recognition towards the imprinted ion. With the increase of Cu/N in the de- positing solution, the selectivity of the prepared composite membrane first increased and then decreased and maximum selectivity coefficient was achieved when the value ofCu：N was 1：8.