Recovery potential of rare earth elements from mining and industrial residues: A review and cases studies

Abstract

Rare earth elements (REE) are critical resources and of strategic importance as they are used in many applications, including emerging technologies. As a result, the demand for REE has continued to increase, to the extent of exceeding their supply. Because conventional deposits can no longer satisfy REE demand for the foreseeable future, intensive research on their recovery from secondary sources is ongoing. The aim of this review is to integrate the most recent findings on the potential for REE recovery from mining and industrial residues. The state-of-the-art of available knowledge is presented for each of the identified REE secondary sources. Pertinent case-related studies are also discussed with a focus on acid mine drainage (AMD) treatment residues, phosphogypsum (PG), and U mine waste. Although these residues hold promising potential as REE secondary sources, further research is required to make the REE recovery economically viable, environmentally respectful, and socially acceptable.