Reclaiming Value from Waste: A Techno-Economic Evaluation of Rare Earth Extraction from Coal Refuse

The rising demand for Rare Earth Elements (REEs) highlights the need for sustainable cost-effective extraction methods, particularly from secondary sources, such as coal-related materials. Recovering REEs from these resources supports domestic supply security while reducing waste. This study evaluates the techno-economic feasibility of producing RE-hydroxide from coal-related materials using a chemical recycling process that recovers 90% of reagents, including 2.5 tons of soda ash and 9.5 tons of water. The process requires $35 million in initial capital investment and yields a Net Present Value (NPV) of $262.4 million with a 42% Rate of Return on Investment (ROROI). Although reagent recycling raises capital and operating costs, increasing recovery to 99%, incorporating byproduct sales, and applying 30% solvent extraction (SX) tolling under favorable market conditions improves profitability─raising NPV and ROROI by 74% and 143%, respectively. The results demonstrate that REE recovery from coal waste is both technically feasible and economically attractive, linking sustainable waste management with a stronger mineral supply chain.