A BIBLIOMETRIC ANALYSIS OF RESEARCH TRENDS IN RARE EARTH ELEMENT (REE) SEPARATION TECHNOLOGIES
DOI:
https://doi.org/10.35631/IJIREV.825007Keywords:
Rare Earth Element, Separation TechnologyAbstract
The escalating worldwide requirement for Rare Earth Elements (REEs), propelled by their indispensable applications in clean energy technologies, electronics, and advanced manufacturing, has intensified research into efficient and sustainable separation technologies. Despite substantial scientific progress, the expanding volume of literature has created challenges in identifying dominant research trends, key contributors, as well as newly emerging thematic developments within this area. This study seeks to bridge this gap by offering an extensive bibliometric examination of REE separation technologies. A systematically compiled dataset was extracted from the Scopus database through the use of advanced search strategies built around two core terms, namely “rare earth element” and “separation technology.” The dataset comprises 1,193 publications spanning the period from 2018 to May 2026. Data cleaning as well as refinement were carried out through OpenRefine, whereas performance analysis and visualization of scientific mapping were conducted using VOSviewer and the Scopus analytical tools. The results demonstrate a pronounced upward trajectory in yearly publication output, with a sharp increase observed after 2021, indicating growing global research interest. China, the United States, and Germany stand out as the principal contributors when assessed through publication volume and citation influence. Meanwhile, keyword co-occurrence mapping identifies dominant themes such as Solvent Extraction (SX), adsorption, and hydrometallurgical processes, alongside emerging topics including green separation technologies and membrane-based systems. Collaboration network analysis further highlights increasing international research partnerships, particularly among technologically advanced economies. To conclude, this study delivers a structured synthesis of the knowledge framework and the shifting research landscape surrounding REE separation technologies, yielding meaningful insights for researchers, policymakers, as well as industry stakeholders to guide future research directions, funding priorities, and innovation strategies in support of sustainable resource development.
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