Reaction Mechanism of AlCl Generated by Carbothermic-chlorination to Produce Aluminum in Vacuum
In different reaction temperatures and system pressures, the reaction mechanism of AlCl generated by carbothermic-chloride process has been investigated by XRD, SEM (EDS) and thermodynamic analysis. The results show that the initial temperatures of Al4O4C and Al4C3 beginning to be formed are 1689.44K and 1712.97K (100Pa), respectively. Al4O4C transformed into Al4C3 at 1724.74K (100Pa). Thermodynamic analysis of carbothermic-chloride reaction suggests that the Gibbs free energy of Al2O3 together with C and AlCl3 to form AlCl is -20.041KJ at 1500K (101Pa). Initial temperatures of A1C1 (g) generated by Al4O4C-AlCl3-C, Al4C3-Al2O3-AlCl3 and Al4O4C-Al4C3-Al2O3-AlCl3-C system in carbothermic-chloride process are 1458.96K, 1377.50K and 1432.82K (100Pa), respectively. The experimental results indicate that Al4O4C and Al4C3 began to be formed by Al2O3-C system over 1693K (50-100Pa) and the contents of those increased with increasing temperature from 1703K to 1853K. Al2O3 and Al4O4C will be transformed into Al4C3 while temperature continues to increase or system pressure down. Experiments have been carried out and demonstrated that reaction among Al2O3-AlCl3-C system didnt occur at 1693K (50-100Pa). Aluminum was gained froml753K to 1853K and 70-150Pa, which shows that Al4O4C and Al4C3 are needed to participate in the process of carbothermic-chloride reaction.
AlCl Alumina Graphite anhydrous-AlCl3 Aluminum Carbothermic reduction Slag
YUAN Hai-bin YANG Bin YU Qing-chun XU Bao-qiang ZHU Yu-yan FENG Yue-bin DAI Yong-nian
National Engineering Laboratory of Vacuum Metallurgy Key Laboratory of Nonferrous Metals Vacuum Meta Institute of Information Engineering and Automation, Kunming University of Science and Technology, K
国际会议
沈阳
英文
39-45
2009-08-24（万方平台首次上网日期，不代表论文的发表时间）