Progress in green and efficient enrichment of rare earth from leaching liquor of ion adsorption type rare earth ores

• Published in: Journal of rare earths Vol. 40; no. 3; pp. 353 - 364
• Main Authors: He, Qiang, Qiu, Jiang, Chen, Jinfa, Zan, Miaomiao, Xiao, Yanfei
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.03.2022
• Subjects: Aluminum; Ion adsorption type rare earth ores; Leaching liquor; Non-ammonia enrichment; Rare earth; Separation; Non-ammonia enrichment; Separation; Leaching liquor; Rare earth; Aluminum; Ion adsorption type rare earth ores
• ISSN: 1002-0721; 2509-4963
• DOI: 10.1016/j.jre.2021.09.011

Ion adsorption type rare earth ores (IATREOs) are a valuable strategic mineral resource in China, which feature a complete composition of fifteen rare earth elements and are rich in medium and heavy rare earth (RE) elements. In the leaching process for recovering rare earth elements from IATREOs, many impurities will be leached together with rare earth elements and enter the leaching liquor. An impurity removal-precipitation enrichment technique is currently applied to selectively recovery rare earth elements from the leaching liquor with the high content of impurities and low concentration of rare earth elements by using ammonium bicarbonate in the industry. However, a high loss of rare earth elements and severe ammonia nitrogen pollution are caused by this process. Therefore, more beneficial impurities removal technologies, mainly for aluminum, and green enrichment technologies with lower pollution are now urgently needed. For this purpose, this paper analyzed two aspects of research progress in recent decades: the green separation of rare earth elements and aluminum from leaching liquor and the green and efficient enrichment of rare earth elements. Finally, an approach for the high-efficiency and green enrichment of rare earth elements from leaching liquor of the IATREOs is proposed in several aspects, including impurity inhibition leaching, neutralization and impurity removal, alkaline calcium and magnesium salt precipitation enrichment, and centrifugal extraction enrichment. The research progress in the green separation of aluminum and the green and efficient enrichment of rare earth elements from the leaching liquor of ion adsorption type rare earth ores are reviewed. The high-efficiency and green approach for enriching rare earth elements from leaching liquor is proposed in several aspects. [Display omitted] •Progress in separation of rare earth and aluminum from leaching liquor of ion adsorption type rare earth ores.•Overview of advantages and disadvantages of various enrichment methods from leaching liquor.•An approach for high-efficiency and green enrichment of rare earth elements from leaching liquor is proposed.