Coal Bottom Ash as a Potential Adsorbent for CO2 Capture

Coal bottom ash (CBA) is the solid residue produced from coal-fired power plant. It is classified as hazardous material, which can cause adverse effect to the environment and public health. In view of the situation, exploring and discovering possible utilization of these coal residues into value-added products has to be performed. Hence, the aim of this paper is to investigate the potential of raw CBA as an adsorbent for carbon dioxide (CO2) gas adsorption. The physicochemical characteristics of CBA were determined using ultimate and proximate analysis, nitrogen adsorption-desorption isotherm, scanning electron microscopy (SEM), and elemental diffraction x-ray (EDX) analysis. CO2 adsorption study was conducted using simulated flue gas by pressure swing adsorption process in a fixed-bed reactor to evaluate the suitability of CBA as an adsorbent material. High carbon content in CBA makes it's become a good precursor for production of carbonaceous adsorbent. Trace elements like calcium, silica and alumina, indicating that the material had a good adsorption capacity. The result indicated that CBA was able to adsorb CO2 with the adsorption capacity of 0.000276 mol CO2/g CBA. As a conclusion, CBA has the potential to be an adsorbent for its application in gas phase especially in CO2 adsorption.