Division of Environmental Science and Engineering, Faculty of Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117576, Singapore.
J Colloid Interface Sci. 2010 May 15;345(2):454-60. doi: 10.1016/j.jcis.2010.01.057. Epub 2010 Jan 28.
This paper examines the characteristics of poly(glycidyl methacrylate) (PGMA) beads functionalized with different aliphatic polyamines as adsorbents and their performance in copper ion adsorption. The four aliphatic polyamines evaluated include ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetetramine (TETA), and tetraethylenepentamine (TEPA). Various analytical tools, including elemental analysis, BET, and XAFS (XANES+EXAFS), were used to characterize the adsorbents in terms of their immobilized amine contents, polyamine densities, and their coordination structures for the adsorption of a typical heavy metal ion, Cu(2+). It was found that the immobilized polyamine densities followed the order of EDA>DETA>TETA>TEPA, but the immobilized amine contents followed the opposite order of TEPA>TETA>DETA>EDA. XAFS analysis for the adsorbents after copper ion adsorption revealed that the average coordination number of copper ion with the nitrogen atoms (in the range between 3 and 4) followed the order of DETA<TETA<EDA<TEPA. Hence, the molecular length and structure of the polyamines appeared to have a great effect on the adsorption performance of the prepared adsorbents. The study leads to the conclusion that among the four aliphatic polyamines, DETA-functionalized PGMA adsorbent was the most efficient one for copper ion removal because of the relatively higher amine content and lower coordination number, easier regeneration, and shorter preparation time of the adsorbent. The results provide some useful information for future studies in the selection of polyamines for adsorbent functionalization.
本文研究了不同脂肪族多胺官能化的聚(甲基丙烯酸缩水甘油酯) (PGMA) 珠作为吸附剂的特性及其在铜离子吸附中的性能。评估的四种脂肪族多胺包括乙二胺 (EDA)、二乙烯三胺 (DETA)、三乙烯四胺 (TETA) 和四乙烯五胺 (TEPA)。采用元素分析、BET 和 XAFS（XANES+EXAFS）等各种分析工具，从固定化胺含量、多胺密度以及它们对典型重金属离子 Cu(2+) 的吸附配位结构等方面对吸附剂进行了表征。结果表明，固定化多胺密度的顺序为 EDA>DETA>TETA>TEPA，但固定化胺含量的顺序则相反，为 TEPA>TETA>DETA>EDA。对吸附铜离子后的吸附剂进行 XAFS 分析表明，铜离子与氮原子的平均配位数（在 3 到 4 之间）的顺序为 DETA<TETA<EDA<TEPA。因此，多胺的分子长度和结构似乎对制备吸附剂的吸附性能有很大影响。研究得出的结论是，在这四种脂肪族多胺中，DETA 官能化 PGMA 吸附剂是去除铜离子最有效的吸附剂，因为其具有较高的胺含量和较低的配位数、更易再生以及更短的制备时间。研究结果为未来选择多胺进行吸附剂功能化提供了一些有用的信息。
