Selective adsorption of Ag+ by ion-imprinted O-carboxymethyl chitosan beads grafted with thiourea–glutaraldehyde
Selective adsorption of Ag+ by ion-imprinted O-carboxymethyl chitosan beads grafted with thiourea–glutaraldehyde
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DOI：
10.1016/j.cej.2014.11.062
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发表时间：
2015-03
影响因子：
15.1
通讯作者：
Menghui Zhang;Yan Zhang;R. Helleur
中科院分区：
文献类型：
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作者：
Menghui Zhang;Yan Zhang;R. Helleur
本研究采用表面印迹和聚合物交联相结合的新技术合成了Ag+印迹硫脲/戊二醛接枝o -羧甲基壳聚糖（ITG-OCMC）微球，该微球对双金属水溶液中Ag+具有极好的选择性吸附能力。结果表明，高水平的羧甲基化和低水平的交联有利于提高银离子的吸收能力。在初始银离子浓度为160.5 mg L−1，生物吸附剂用量为1.0 g L−1的条件下，在40℃条件下，银离子的最大吸收量为156.32 mg g−1。Langmuir等温线和Lagergren伪二阶动力学可以用来描述Ag+的吸附过程。FT-IR和XPS分析证实，Ag+在ITG-OCMC珠表面通过> c双键、胺、羧基和羟基螯合发生选择性吸附。
In this study, a novel technique combining surface imprinting and polymer crosslinking was applied to synthesize the Ag+-imprinted thiourea/glutaraldehyde grafted O-carboxymethyl chitosan (ITG-OCMC) beads which demonstrate extremely good selective adsorption of Ag+from a bimetallic aqueous solution. Results indicated that high degree of carboxymethylation and low level of crosslinking would help to achieve higher uptake capacity of Ag+. The maximum uptake of Ag+was found to be 156.32 mg g−1at 40 °C with an initial Ag+concentration of 160.5 mg L−1and the biosorbent dosage of 1.0 g L−1. Langmuir isotherm and Lagergren’s pseudo-second-order kinetic can be used to describe the sorption process of Ag+. Analyses from FT-IR and XPS confirmed that selective adsorption of Ag+took place on the surfaces of ITG-OCMC beads by chelation through >Cdouble bondS, amine, carboxyl and hydroxyl groups.