Department of Green Chemistry, School of Engineering Science, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli, Finland.
Department of Green Chemistry, School of Engineering Science, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli, Finland.
Chemosphere. 2018 Aug;204:413-430. doi: 10.1016/j.chemosphere.2018.04.053. Epub 2018 Apr 12.
Over the past few decades, removal and recovery of Lanthanum (La) have received great attention due to its significance in different industrial processes. In this review, the application of various adsorbents viz. biosorbents, commercial and hybrid materials, nanoparticles, nanocomposites etc. have been summarized in terms of the removal and recovery of La. The influence of various operating parameters including pH, dosage, contact time, temperature, coexisting ions, adsorption kinetics, isotherm and thermodynamics were investigated. Statistical analysis of the obtained data revealed that 60% and 70% of the authors reported an optimum pH of 4-6 and a dose of 1-2 g/L, respectively. It can be concluded on the basis of an extensive literature survey that the adsorbent materials (especially hybrids nanocomposites) containing carboxyl, hydroxyl and amine groups offered efficient La removal over a wide range of pH with higher adsorption capacity as compared to other adsorbents (e.g., biosorbents and magnetic adsorbents). Also, in most cases, equilibrium and kinetics were followed by Langmuir and pseudo second-order model and adsorption was endothermic in nature. To evaluate the adsorption efficiency of several adsorbents towards La, desorption and regeneration of adsorbents should be given due consideration. The main objective of the review is to provide an insight into the important factors that may affect the recovery of La using various adsorbents.
在过去的几十年中，由于镧在不同工业过程中的重要性，其去除和回收受到了极大的关注。在这篇综述中，总结了各种吸附剂（如生物吸附剂、商业和混合材料、纳米粒子、纳米复合材料等）在镧的去除和回收方面的应用。研究了各种操作参数（包括 pH 值、用量、接触时间、温度、共存离子、吸附动力学、等温线和热力学）的影响。对获得的数据进行统计分析表明，60%和 70%的作者分别报告了最佳 pH 值为 4-6 和剂量为 1-2 g/L。根据广泛的文献调查可以得出结论，与其他吸附剂（如生物吸附剂和磁性吸附剂）相比，含有羧基、羟基和胺基的吸附剂材料（特别是混合纳米复合材料）在较宽的 pH 范围内提供了高效的镧去除，具有更高的吸附容量。此外，在大多数情况下，平衡和动力学遵循朗缪尔和准二级模型，吸附是吸热的。为了评估几种吸附剂对镧的吸附效率，应适当考虑吸附剂的解吸和再生。本综述的主要目的是深入了解可能影响使用各种吸附剂回收镧的重要因素。
