硅胶表面铜(Ⅱ)离子印迹聚乙烯亚胺的制备及结合特性研究

通过γ-氯丙基三甲氧基硅烷的媒介,将聚乙烯亚胺(PEI)偶合接枝到硅胶微粒表面,形成了化学键联的复合材料PEI/SiO2;以Cu2+为模板离子,以环氧氯丙烷为交联剂,通过配位键作用,对化学键合在硅胶表面的PEI大分子链进行了离子印迹,制备了复合型Cu2+印迹材料IIP-PEI/SiO2;采用静态与动态两种方法研究了IIP-PEI/SiO2对Cu2+的结合特性,并考察了主要印迹条件Cu2+浓度及环氧氯丙烷用量对印迹材料吸附性能的影响.结果表明,Cu2+印迹材料IIP-PEI/SiO2对Cu2+具有强的记忆识别能力,主要表现在两个方面,(1)对Cu2+的结合量大,IIP-PEI/SiO2对Cu2+的吸附容量比印迹前复合材料PEI/SiO2提高了近2倍;(2)对Cu2+的选择性高,相对于Cd2+,IIP-PEI/SiO2对Cu2+的选择性系数为83.79,相对于Zn2+,IIP-PEI/SiO2对Cu2+的选择性系数为80.21.另外印迹材料IIP-PEI/SiO2具有优良的洗脱与再生性能.

STUDIES ON PREPARATION OF ION-IMPRINTED POLYETHYLENEIMINE ON SILICA GEL PARTICLES AND BINDING PROPERTIES FOR METAL IONS

Polyethyleneimine (PEI)was grafted onto the surface of silica gel particles via the coupling effect of γ-chloropropyltrimethoxysilane (CP),and the novel composite material PEI/SiO_2 with chemical bond linkage was prepared.Then the molecular imprinted polyethyleneimine on the surface of silica gel was prepared using Cu~ 2+ as template ions and epichlorohydrin (ECH)as crosslinking agent via coordination bond effects,and composite ionic imprinted material IIP-PEI/SiO_2 was obtained.Both static and dynamic methods (i.e.batch and column methods)were adopted to study the binding properties of IIP-PEI/SiO_2 for Cu~ 2+ ,and the effects of main imprinting conditions,the concentration of Cu~ 2+ and the used amount of epichlorohydrin,on the binding properties of IIP-PEI/SiO_2 were examined.The experiment results show that the ionic imprinted material IIP-PEI/SiO_2 possesses strong recognizing ability for Cu~ 2+ ,and the ability is displayed in two aspects:(1)IIP-PEI/SiO_2 has high selectivity for Cu~2+ ,in relation to Cd~2+ the selectivity coefficient of IIP-PEI/SiO_2 for Cu~2+ is 83.79,and in relation to Zn~2+ the selectivity coefficient of IIP-PEI/SiO_2 for Cu~ 2+ is 80.21;(2)The binding amount of Cu~ 2+ on IIP-PEI/SiO_2 is much greater than that on PEI/SiO_2,which was not ion-imprinted,and the former is two times greater than the latter.Besides,the ionic imprinted material IIP-PEI/SiO_2 has excellent elution property,and it is easy to be regenerated and reused.