Extracting Rare Earth Elements Using Food-Grade Acids

Rare earth elements (REE) are 17 metallic elements found in the middle of the Periodic Table, that are known for their conductive and magnetic properties. Studies have shown that REE can be extracted from coal fly ash, which is the fine particle ash created from the combustion of coal. This extraction is usually done using concentrated inorganic acids. Though this process works, using strong acids creates environmental sustainability concerns. This study represents the early stages of investigation of the efficiency of extracting REE from coal fly ash using food-grade organic acids and supercritical CO2.