Rare Earth Elements Recovery from Primary and Secondary Resources Using Flotation: A Systematic Review
Source abstract
Abstract
Rare earth minerals (REMs) contain rare earth elements (REEs) that are important in modern technologies due to their unique magnetic, phosphorescent, and catalytic properties. However, REMs are not only non-renewable resources but also non-uniformly distributed on the Earth’s crust, so the processing of REE-bearing secondary resources via recycling is one potential route to ensure the long-term sustainability of REE supply. Flotation—a method that separates materials based on differences in their surface wettability—is a process applied for both mineral processing and recycling of REEs, especially when the particles are fine and/or a high-purity product is required. In this review, studies about rare earth flotation from 2012 to 2021 were systematically reviewed using the PRISMA guideline. It was found that most REM flotation research works focused on finding better collectors and depressants while, for recycling, studies on advanced flotation techniques like froth flotation, ion flotation, solvent sublation, electroflotation, and adsorbing colloid flotation with an emphasis on the recovery of dissolved REEs from aqueous solutions dominated.
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Research context
OpenAlex topics: Extraction and Separation Processes · Minerals Flotation and Separation Techniques · Recycling and Waste Management Techniques
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Mining and Petroleum Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand
Department of Mining and Materials Engineering, Faculty of Engineering, Prince of Songkla University, Songkhla 90110, Thailand
Department of Earth Sciences, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand
Division of Sustainable Resources Engineering, Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan
Department of Materials and Resources Engineering Technology, College of Engineering, Mindanao State University–Iligan Institute of Technology, Iligan City 9200, Philippines
Resource Processing and Technology Center, Research Institute of Engineering and Innovative Technology, Mindanao State University–Iligan Institute of Technology, Iligan City 9200, Philippines
Funding
Chulalongkorn University
References (100+)
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