真空热还原法制备金属锂的研究进展

Research Progress on Preparation of Lithium Metal by Vacuum Thermal Reduction

熔盐电解法是生产金属锂的传统方法,但该法存在原料成本高、阳极会生成氯气、产品中钠含量高等问题。真空热还原法是将锂还原后,再利用饱和蒸汽压的差异来提取金属锂,产品分离简单,且产品中的钠含量较低,具有成本较低、工艺简单、产品纯度高、生产过程中基本无污染性气体产生等优点。文章综述了碳热还原、硅热还原和铝热还原等真空热还原法炼锂工艺的技术现状及存在的问题,介绍了一种以氢氧化锂为原料副产高白氢氧化铝的新型铝热还原炼锂新工艺,旨在为真空金属热还原法炼锂开拓新路径。

Molten salt electrolysis is a traditional method for lithium metal production,but it has some problems such as high cost of raw materials,the chlorine gas produced on anode and high sodium content in product.The vacuum thermal reduction method is to extract metal lithium by the difference of saturated vapor pressure after lithium is reduced.The product separation is simple,and the sodium content in the product is low.It has the advantages of low cost,simple process,high purity and no pollution gas in the production process.In this paper,the present situation and existing problems of many vacuum thermal reduction methods of lithium,such as carbon thermal reduction method,silicon thermal reduction method and aluminum-thermal reduction method are reviewed,and a novel aluminum-thermal reduction method is introduced,this process produces lithium from lithium hydroxide as raw material,with high whiteness aluminum hydroxide as a by-product,which is aimed to develop a new way for vacuum metal thermal reduction of lithium.