摘要
Due to the unique physical and chemical properties,rare earth elements(REEs)play a significant role in the high-tech field.In the past few decades,the rare earth reserve in China has been gradually decreasing and more pressure has been exerted on the global rare earth supply for the increasing demand of REEs,which indicates that it is essential to recycle secondary resources to meet the rare earth demand.As for rare earth molten salt electrolytic slag(REMES),although its high rare earth content has potential huge economic value,its high fluorine content of approximately 10 wt%-20 wt%can pollute the environment.Three methods are used to treat REMES.Hydro metallurgical and pyro-hydrometallurgical methods have gotten a big success for solving most of the hydrometallurgical problems,while some problems,like long route and waste water,need to be solved.Vacuum distillation is a new and promising method with a short process due to its harmlessness and high efficiency,but has shortcomings such as high energy consumption and material adaptability.This review presents these above three treatment methods,and the challenges and chances of using the recovery technique of REMES in an environmentally friendly way.
基金
Project supported by the National Key R&D Program of China(2020YFC1909003)。
