A comprehensive review on treatment and recovery of rare earth elements from wastewater: Current knowledge and future perspectives

Abstract

As the significance of rare earth elements (REEs) as a strategic resource in the industrial economy and the scarcity of the resource itself gain prominence worldwide, technologies for capturing and recovering REEs from wastewater are crucial for a sustainable future. To gain a comprehensive insight into research focuses and emerging trends related to the recovery of REEs from wastewater, the Web of Science Core Collection (WOSCC) database was used for the literature search. Bibliometrix, VOSviewer, and CiteSpace software were employed for bibliometric analysis of research literature published between 2000 and 2023, investigating aspects such as the prominent contributing countries/regions, prolific authors, source journals, and major research institutions. The results revealed a steady increase in research pertaining to the recovery of REEs from wastewater during the studied period. China, India, and the USA were identified as leading contributors, with the Chinese Acad Sci being recognized as the most productive institution. Based on the co-occurrence and burst analysis of keywords, it was found that the adsorption and solvent extraction of REEs from wastewater currently dominate current research, with the development of emerging technologies such as the electrochemical method and biological extraction method representing potential future hotspots. Additionally, emerging types of highly selective and high-capacity adsorbents for REEs are anticipated to become a prominent area of interest. This paper provided a comprehensive overview of the current state of the recovery of REEs from wastewater and forecasts future trends, offering a valuable reference for understanding the evolving dynamics in this field.