Distribution of Rare Earth Elements in Coal and Coal Fly Ash

Abstract

Coal fly ash is one of the potential resource for the recovery of REEs from it. Coal fly ash is obtained as a by-product after combustion of coal in thermal power plant. On an average, the coal-based fly ash throughout the world contains around 400 mg/kg of REEs. As we know that energy is the basic requirement for the overall development of nations, it plays a very crucial role in their economic development. Developing countries are dependent on coal as natural resources for electricity production by thermal power plant which generate large amount of coal fly ash as a secondary product. About 70–75% of India’s and 40–45% of global energy requirement are fulfilled by coal-based thermal power plant which eventually produces a large amount of fly ash. India utilizes 60–70% and world utilizes about 45–50% of coal fly ash in different areas like cement industry, in roads and embankment construction, Mine filling, making bricks, and tiles. The rest amount of fly ash remains unutilized and is a global concern to address. Abundance of REEs in coal fly across the world is about 5–10 times more than the concentration of REEs in coal. CFA is a very potential source of rare earth elements. This chapter reviews the detailed study of coal and coal fly ash, distribution of REEs in coal, coal-based fly ash, and different methods for the recovery of REEs from coal fly ash.