Kinetics of Roasting of High Aluminum Content Coal Fly Ash with Sodium Carbonate and Acid Leaching for Extraction of Aluminum
LIU Neng-sheng PENG Jin-hui ZHANG Li-bo LIN Jin
Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming Faculty of Materials and Metallurgical Engineering, Kunming University of Science and Technology Faculty of Materials and Metallurgical Engineering, Kunming University of Science and Technology Engineering training center, Kunming University of Science and Technology
Abstract:High aluminum content coal fly ash (CFA) from Inner Mongolia was roasted with Na2CO3, and the roasted material leached by HCl solution for extraction of aluminum. The effects of roasting temperature and time, and mass ratio of Na2CO3 to CFA on the leaching rate of aluminum were examined. The process kinetics and mechanisms of roasting and acid leaching were analyzed. The results showed that at high roasting temperature, the reaction of mullite (Al6Si2O13) and SiO2 in CFA with Na2CO3 resulted in formation of NaAlSiO4, Al2O3 and Na2SiO3, which could be dissolved in HCl solution. After acid leaching, the leaching rate of aluminum reached more than 94.99%. The Crank-Ginstling-Braunshtein model could be used to correlate the experimental data of roasting process, and the apparent activation energy was calculated as 117.06 kJ/mol. The reaction rate was controlled by solid-film diffusion.
刘能生 彭金辉 张利波 蔺琎. 高铝粉煤灰碳酸钠焙烧与酸浸提铝的动力学[J]. 过程工程学报, 2016, 16(2): 216-221.
LIU Neng-sheng PENG Jin-hui ZHANG Li-bo LIN Jin. Kinetics of Roasting of High Aluminum Content Coal Fly Ash with Sodium Carbonate and Acid Leaching for Extraction of Aluminum. Chin. J. Process Eng., 2016, 16(2): 216-221.