Preparing Alumina by an Electrolytic Method from Sulfuric Acid Leachate of Coal Fly Ash

Coal fly ash (CFA) is a solid waste from burning coal in power plants and has caused serious environmental problems. From this study, a three-staged process: sulphating-roasting, leaching and electrolysis, to produce alumina from coal fly ash in an environmentally-friendly manner is proposed. In this work, the key process of electrolysis was investigated in detail, batch experiments were performed to evaluate the potential effects of important parameters such as electrode distance. The electrolytic products were analyzed by XRD, XRF, SEM and Particle size distribution (PSD). The results showed that the electrolysis products were Al(OH)3 which can be used for aluminum reduction. Moreover, the electrolysis mechanisms in sulfuric acid leachate are also discussed.