Overview on the Potential of Coal-Based Bottom Ash as Low-Cost Adsorbents

The accelerating demand of energy in the world has resulted in increasing numbers of installation of coal-fired power plants. With growth in coal burning power stations, huge amounts of coal bottom ash considered as hazardous materials are anticipated to be produced. At present, coal ash residues are conventionally disposed in an on-site disposal system such as land-fill and in ash pond without any commercialization purposes. The massive generation of coal bottom ash in power plants causes a variety of environmental pollutions, with regards to presence of alkaline heavy metals and their leaching problems. In addition, huge accumulation of bottom ash results in handling and storage problems, such as inadequate spaces or facilities to hold the coal burning residues. Accordingly, a review on the prospect of coal bottom ash utilization as adsorbent material is elaborated. The physical and chemical properties of the bottom ash are discussed for a good understanding of the physiochemical characteristics and suitability as an adsorbent. A comprehensive discussion on the potential utilization of bottom ash is significant, as it helps to alleviate environmental hazards and convert them into valuable end-products.