Radiological Safety Division.
Chemical Engineering Division, Bhabha Atomic Research Centre, Mumbai, India.
J Hazard Mater. 2017 Apr 15;328:1-11. doi: 10.1016/j.jhazmat.2017.01.001. Epub 2017 Jan 3.
A novel chelating resin obtained via growth of PAMAM dendron on surface of styrene divinyl benzene resin beads, followed by diglycolamic acid functionalization of the dendrimer terminal. Batch experiments were conducted to study the effects of pH, nitric acid concentration, amount of adsorbent, shaking time, initial metal ion concentration and temperature on U(VI) and Th(IV) adsorption efficiency. Diglycolamic acid terminated PAMAM dendrimer functionalized styrene divinylbenzene chelating resin (DGA-PAMAM-SDB) is found to be an efficient candidate for the removal of U(VI) and Th(IV) ions from aqueous (pH >4) and nitric acid media (>3M). The sorption equilibrium could be reached within 60min, and the experimental data fits with pseudo-second-order model. Langmuir sorption isotherm model correlates well with sorption equilibrium data. The maximum U(VI) and Th(IV) sorption capacity onto DGA-PAMAMG-SDB was estimated to be about 682 and 544.2mgg respectively at 25°C. The interaction of actinides and chelating resin is reversible and hence, the resin can be regenerated and reused. DFT calculation on the interaction of U(VI) and Th(IV) ions with chelating resin validates the experimental findings.
一种新型螯合树脂，通过在苯乙烯-二乙烯基苯树脂珠表面生长 PAMAM 树枝状大分子，然后对树枝状大分子末端进行二甘醇酸官能化得到。通过批实验研究了 pH 值、硝酸浓度、吸附剂用量、振荡时间、初始金属离子浓度和温度对 U(VI)和 Th(IV)吸附效率的影响。发现二甘醇酸封端的 PAMAM 树枝状大分子功能化苯乙烯-二乙烯基苯螯合树脂（DGA-PAMAM-SDB）是从水溶液（pH>4）和硝酸介质（>3M）中去除 U(VI)和 Th(IV)离子的有效候选物。吸附平衡可在 60 分钟内达到，实验数据符合拟二级模型。Langmuir 吸附等温线模型很好地符合吸附平衡数据。在 25°C 下，DGA-PAMAM-SDB 对 U(VI)和 Th(IV)的最大吸附容量分别约为 682 和 544.2mgg。锕系元素与螯合树脂的相互作用是可逆的，因此，树脂可以再生和重复使用。U(VI)和 Th(IV)离子与螯合树脂相互作用的 DFT 计算验证了实验结果。
