Study on physico-chemical properties, mineral matters and leaching characteristics of some Indian coals and fly ash

Six high sulphur coal samples along with two fly ash samples were characterized by using X-ray diffraction (XRD), Energy Dispersive x-ray Fluorescence (EDXRF), Atomic Absorption Spectroscopy (AAS), Fourier Transform Infrared (FT-IR) and Scanning Electron Spectroscopy (SEM) techniques to interpret their mineral matters and inorganic constituents. The proximate, ultimate and sulfur analyses of the coal and fly ash samples were also performed to know their possible aspects of utilization. Significant amount of silicate/clay minerals along with other elements are found to be present in these coals and fly ash samples. The SEM micrographs showed the presence of pyrite and marcasite in different forms including clusters of pyrites in the coals. The leaching characteristics of the coal and fly ash samples showed the mobilization of some potentially hazardous elements (PHEs) from them. Mercury was found to be leached out with ~0.50 ppm from fly ash samples in water.