Adsorption of lanthanum by magnetic alginate‐chitosan gel beads
Adsorption of lanthanum by magnetic alginate‐chitosan gel beads
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DOI：
10.1002/jctb.2522
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发表时间：
2011-03
影响因子：
3.4
通讯作者：
Dong-bei Wu;Ling Zhang;Li Wang;Baohui Zhu;Li-yan Fan
中科院分区：
文献类型：
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作者：
Dong-bei Wu;Ling Zhang;Li Wang;Baohui Zhu;Li-yan Fan
背景：稀土元素在先进材料中的大量应用加剧了环境污染的风险。本文报道了新型海藻酸盐-壳聚糖磁性凝胶珠的制备及其在水溶液中吸附镧离子的应用。结果：通过在海藻酸盐-壳聚糖复合吸附剂上负载氧化铁纳米颗粒，制备了平均粒径为0.85±0.05 mm的稳定磁性藻酸盐-壳聚糖凝胶珠。测试了所制备的微球对水溶液中镧离子的吸附性能。研究发现，水溶液pH、接触时间、金属离子浓度、离子强度和温度等参数对吸附均有影响。10 h达到吸附平衡，最大吸收量为97.1 mg g−1。通过对pH、FTIR和XPS数据的分析，提出镧的吸附是通过阳离子交换、静电相互作用和表面络合等机制进行的，其中氧原子是主要的结合位点。此外，镧离子可以选择性地与水溶液中共存的贱金属离子Pb （II）、Cd （II）、Co （II）、Ni （II）和Cu （II）分离。结论：制备的海藻酸盐-壳聚糖磁性凝胶珠对镧具有较高的吸附能力和选择性，可用于吸附回收水溶液中的镧。版权所有©2010化工学会
BACKGROUND:The risk of environmental pollution is aggravated by the increasing application of considerable amounts of rare earth elements in advanced materials. This paper reports the preparation of novel magnetic alginate–chitosan gel beads and their application for adsorption of lanthanum ions from aqueous solution.RESULTS:Stable magnetic alginate–chitosan gel beads with average diameter 0.85 ± 0.05 mm were prepared by loading iron oxide nanoparticles onto a combined alginate and chitosan absorbent. The performance of the prepared beads for the adsorption of lanthanum ions from aqueous solution was tested. It was found that various parameters, such as aqueous pH, contact time, metal ion concentration, ion strength and temperature, have an effect on the adsorption. Adsorption equilibrium was reached in 10 h and the maximum uptake capacity was 97.1 mg g−1. From the analysis of pH, FTIR and XPS data, it is proposed that lanthanum adsorption proceeds through mechanisms of cation exchange, electrostatic interaction and surface complexation, with the oxygen atoms the main binding sites. In addition, lanthanum ions could be selectively separated from coexisting base metal ions such as Pb (II), Cd (II), Co (II), Ni (II) and Cu (II) in the aqueous solution.CONCLUSION:The prepared magnetic alginate–chitosan gel beads exhibit high uptake capacity and selectivity for lanthanum sorption, and thus can be used for adsorptive recovery of lanthanum from aqueous solutions. Copyright © 2010 Society of Chemical Industry