Bioleaching for the recovery of rare earth elements from industrial waste: A sustainable approach
Khyati Joshi, Sara Magdouli, Satinder Kaur Brar
Abstract
• Rare Earth Elements (REEs) are vital for modern technology and renewable energy. • Industrial waste is a promising alternative for REEs. • Conventional REE extraction methods are environmentally harmful. • Bioleaching offers a sustainable, eco-friendly method for REEs recovery. • Bioleaching requires optimization for higher REE recovery efficiency. Rare earth elements (REEs) play an important role in various high-tech technologies, including renewable energy systems, electronics, and catalytic converters. The increasing demand for REEs, coupled with their limited and geographically constrained natural deposits, necessitates the exploration of alternative sources. Industrial wastes including electronic waste, phosphogypsum, and coal fly ash are rich in REEs and present a promising reservoir for these critical elements. Typically, REE extraction is carried out using conventional methods such as solvent extraction, roasting, and acid leaching. However, these methods are not eco-friendly and pose environmental challenges, such as dust generation, high energy requirements, and harmful gas emissions. Therefore, there is a pressing need to explore alternative, eco-friendly methods to overcome these challenges. Bioleaching offers a sustainable solution to solubilize REEs from industrial waste, presenting a greener approach to resource recovery. This review comprehensively discusses the bioleaching of REEs from various industrial waste streams. It critically discusses the challenges faced in bioleaching, such as process scalability and efficiency, and explores prospects, emphasizing the potential of bioleaching to revolutionize the REE supply chain.