Abstract:

Rare earth metals are regards as the essential strategic resources in China due to the unique roles in high-precision products. The separation and purification of rare earth elements is particularly important in order to satisfy the high purity criterion of products. Membrane separation technology is a highly efficient, low power consuming and environmental-friendly separation method, which can be widely used in extensive fields. In addition, their application in rare earth metal separation can efficiently improve the separation properties and greatly decrease the serious environment pollutions caused by the rare earth separation and its related industries. Hence, the scientific researches on these issues are highly crucial but still facing challenges. In this review, three kinds of membrane separation strategies, including ion imprinted membrane, polymer inclusion membrane and liquid membrane, were systematically introduced. Moreover, the preparation methods and separation properties of membrane materials were summarized, and the characteristics, advantages and disadvantages of subdivision types of membrane technology were discussed and compared. Furthermore, Ion imprinted membrane exhibited the great advantages in separation selectivity, but further improvement of adsorption capacity was highly needed, which was also the research focus of membrane separation technology in the next few years. Polymer inclusion membrane and liquid membrane separation technology showed the great potentials in the rare earth separation using membrane technology in the industrial application because it can flexibly adjust the type and quantity of active sites targeting at rare earth separation according to the type and amount of extractant.

Key words: rare earth, membrane separation, ion imprinted, polymer inclusion membrane, liquid membrane

摘要：

稀土金属元素是我国重要的战略资源，因其在高精尖产品中的独特作用，稀土金属元素的分离纯化显得格外重要。膜分离技术是一种高效率、低能耗、环境友好的分离手段，在众多领域应用广泛，将其用于稀土金属分离可明显提升分离效率，降低稀土工业对环境的破坏，但目前的研究尚处于起步阶段，将面临较多挑战。本文介绍了膜技术分离稀土金属的三种策略，包括离子印迹膜、聚合物包合膜和液膜，总结了膜材料的制备方法和分离性能，分析比较了膜技术细分类型的特点和利弊。本文还指出离子印迹膜的选择分离性优势巨大，但在吸附容量上仍有提升空间，也是未来几年膜分离技术的研究重点；聚合物包合膜和液膜分离技术，可根据萃取剂类型和用量灵活调整活性位点种类和数量，在膜技术分离稀土金属的工业化应用方面具有较大潜力。

关键词: 稀土金属, 膜分离, 离子印迹, 包合膜, 液膜