Sustainable rare earth extraction from phytomining by rapid electrothermal calcination

Rare earth elements (REE) are indispensable to the clean energy and advanced electronics industries, yet conventional mining often entails substantial environmental and energy costs. Phytomining, which harnesses the ability of hyperaccumulator plants to concentrate REE from soil, offers a promising sustainable alternative. However, the downstream recovery of REE from plant biomass remains inefficient and resource-intensive. In this study, we introduce a rapid electrothermal calcination (REC) strategy for REE-enriched biomass, which enables fast thermal activation (e.g., 1000 °C for 20 s) and improves REE extractability through dilute acid leaching, with extraction efficiencies of up to ~97%. The REC process is versatile across various organic hyperaccumulator matrices, as demonstrated using Blechnum orientale and Dicranopteris linearis. Comparative life-cycle analyses reveal that REC reduces carbon emissions by over 70% relative to conventional furnace-based methods. These results establish REC as a sustainable and scalable platform for advancing circular REE recovery via phytomining. The downstream recovery of rare earth elements from plant biomass via phytomining remains inefficient and resource-intensive. This study introduces a rapid electrothermal calcination strategy for rare earth enriched-enriched biomass, improving REE extractability through dilute acid leaching.