China turns coal waste into source of lithium, gallium, germanium

China is pioneering the extraction of critical metals—including lithium, gallium, germanium, and aluminium—from coal waste, specifically coal gangue (rock embedded in coal seams) and fly ash (fine particulate from burning). The country's existing coal production lines already integrate washing, chemical processing, and power generation, providing a robust industrial foundation for resource recovery. This approach addresses both the growing demand for metals driven by the new energy industry and the environmental burden of stockpiling coal waste, traditionally used only as low-value cement additives.

Dai Shifeng, a professor at China University of Mining and Technology-Beijing and a member of the Chinese Academy of Sciences, told China Energy News that coal refuse contains a variety of metal elements and could become a vital source of critical metal supply. While the US, Australia, and Russia are also researching metal extraction from coal, China already has commercial-scale capabilities, particularly for germanium. However, Dai cautioned that success requires close tracking of coal quality and composition, as blending different coal sources before combustion changes the metal content in fly ash, complicating extraction. This effort positions China to reduce reliance on imported critical metals for its advanced manufacturing and clean energy sectors.