摘要
采用螯合电导滴定法研究了聚乙烯亚胺(PEI)与Zn2+、Cd2+的配合过程,提出了PEI与各种金属离子所形成螯合物的可能结构;通过γ-氯丙基三甲氧基硅烷媒介,将PEI偶联接枝在硅胶微粒表面,制备了复合型螯合吸附材料PEI/SiO2;研究了PEI/SiO2对Zn2+、Cd2+等重金属离子的吸附性能。结果表明,水溶性聚胺PEI与Zn2+、Cd2+等离子都能定量地形成四配位的水溶性螯合物,且配合过程速度较快;PEI/SiO2复合型螯合吸附材料对Zn2+、Cd2+都具有强的螯合吸附能力;等温吸附数据符合Langmuir方程,且吸附容量随温度升高而增大;pH对吸附过程有很大的影响,pH=7时,吸附容量最高。
The complexing processes between linear polyethyleneimine （PEI） with Zn^2＋ and Cd^2＋ were studied by using chelation-conductivity titration method, and the structures of these chelates of PEI with various metal ions were proposed. PEI was grafted on silica particles used γ-chloropropyl trimethoxy silane as coupling agent, and the PEI/SiO2 composite with chelating adsorption properties was prepared. The adsorption properties of PEI/SiO2 for Zn^2＋ and Cd^2＋ were investigated. The experiment results show water-soluble chelates with four-coordinated Zn^2＋ or Cd^2＋ ions were quantitatively generated from the reactions of PEI and Zn^2＋ or Cd^2＋ . PEI/SiO2 possesses strong chelation adsorption ability for Zn^2＋ and Cd^2＋ , and the adsorption rates are fast. The data of isothermal adsorption matched well with Langmuir equation. As the adsorption capacity increased with temperature, the chelating adsorption is likely to be an endothermic process. The pH of solutions had a great influence on the adsorption amount, and there was a maximum adsorption capacity when pH = 7.
出处
《化学通报》
CAS
CSCD
北大核心
2006年第3期201-206,共6页
Chemistry
关键词
聚乙烯亚胺
螯合吸附
锌
镉
硅胶
Polyethyleneimine, Chelating adsorption, Zinc ion, Cadmium ion. Silica gel
