Environmental Review of Coal Ash as a Resource for Rare Earth and Strategic Elements

Recently, prices of strategic minerals and rare earth elements have been rising dramatically due to global supply shortages and increasing demands. These metals are integral components of advanced technologies, such as, cell-phones, wind turbines, permanent magnets, and semi-conductors. The relative scarcity of these valuable elements has prompted many companies to search for new mineral sources. In addition to new mining ventures and electronic recycling programs, coal ash has been suggested as a possible large untapped resource. It is well-known that coal ash contains many common metals (e.g., Al, As, Cr, Ni, Se) but some coal ashes also contain elevated concentrations of rare earth and strategic metals (e.g., Ce, La, Ga, Ge). Several companies are exploring methods to extract rare metals from coal ash and investigating whether coal ash processing can serve as an economical and environmentally friendly alternative to traditional mining. As this new use for coal ash develops, it will be important to consider potential environmental impacts. In this presentation we explore coal ash as a source of rare earth and strategic minerals, discuss chemical extraction procedures, and highlight environmental considerations associated with these processes. 2013 World of Coal Ash (WOCA) Conference April 22-25, 2013 in Lexington, KY http://www.flyash.info/