State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 155 Yangqiao Road West, Fuzhou, 350002, PR China.
Nanoscale. 2012 Apr 7;4(7):2423-30. doi: 10.1039/c2nr11993e. Epub 2012 Feb 27.
This work aims at the investigation of nano-Mg(OH)(2) as a promising adsorbent for uranium recovery from water. Systematic analysis including the uranium adsorption isotherm, the kinetics and the thermodynamics of adsorption of low concentrations of uranyl tricarbonate (0.1-20 mg L(-1)) by nano-Mg(OH)(2) was carried out. The results showed a spontaneous and exothermic uranium adsorption process by Mg(OH)(2), which could be well described with pseudo second order kinetics. Surface site calculation and zeta potential measurement further demonstrated that UO(2)(CO(3))(3)(4-) was a monolayer adsorbed onto nano-Mg(OH)(2) by electrostatic forces. Accordingly, the adsorption behavior met the conditions of the Langmuir isotherm. Moreover, in most of the reported literature, nano-Mg(OH)(2) had a higher UO(2)(CO(3))(3)(4-) adsorption affinity b, which implied a higher adsorption amount at equilibrium in a dilute adsorbate system. The significance of the adsorption affinity b for choosing and designing adsorbents with respect to low concentration of resources/pollutants treatment has also been assessed.
本工作旨在研究纳米 Mg(OH)(2) 作为一种从水中回收铀的有前途的吸附剂。通过纳米 Mg(OH)(2) 对低浓度的三碳酸铀酰（0.1-20 mg L(-1)) 进行了铀吸附等温线、动力学和热力学的系统分析。结果表明，Mg(OH)(2) 对铀的吸附是自发的放热过程，可用准二级动力学很好地描述。表面位点计算和zeta 电位测量进一步表明，UO(2)(CO(3))(3)(4-) 是通过静电力单层吸附在纳米 Mg(OH)(2)上的。因此，吸附行为符合 Langmuir 等温线的条件。此外，在大多数报道的文献中，纳米 Mg(OH)(2) 对 UO(2)(CO(3))(3)(4-) 的吸附亲和力 b 更高，这意味着在稀吸附剂体系中，平衡时的吸附量更高。还评估了吸附亲和力 b 在选择和设计用于处理低浓度资源/污染物的吸附剂方面的意义。
