Iron-Rich Sintered Glass-Ceramics from Industrial Wastes

In this study, sintered glass-ceramics made up of jarosite (a hazardous industrial waste) have been obtained by sintering high-iron-content glasses. Thermal gravimetry and differential thermal analysis, carried out in different atmospheres, have been utilized to explain the phase formations in the volume and iron oxidation on the surface of the glass particles. Low-angle XRD technique has been used to investigate the distribution of the phases formed on the surface of the glass during heating. The variation of density of the powder and bulk samples has been used to investigate the kinetics of phase transformation. The value of the Avrami constant, n, has been obtained as 1.33, which corresponds to the three-dimensional diffusion growth on a fixed number of nuclei. The sinter-crystallization process has been defined to yield a 40 wt% crystal phase. The results of this study have opened the possibility of preparing glass-ceramics with an original appearance, somewhat similar to that of granite, by reevaluating industrial wastes.