Rare Earth Elements Recovery from Primary and Secondary Resources Using Flotation: A Systematic Review

Rare earth minerals (REMs) contain rare elements (REEs) that are important in modern technologies due to their unique magnetic, phosphorescent, and catalytic properties. However, REMs not only non-renewable resources but also non-uniformly distributed on the Earth’s crust, so processing of REE-bearing secondary via recycling is one potential route ensure long-term sustainability REE supply. Flotation—a method separates materials based differences surface wettability—is a process applied for both mineral REEs, especially when particles fine and/or high-purity product required. In this review, studies about flotation from 2012 2021 were systematically reviewed using PRISMA guideline. It was found most REM research works focused finding better collectors depressants while, recycling, advanced techniques like froth flotation, ion solvent sublation, electroflotation, adsorbing colloid with an emphasis recovery dissolved REEs aqueous solutions dominated.