(1. 昆明理工大学 冶金与能源工程学院 真空冶金国家工程实验室，昆明 650093；
2. 昆明理工大学 理学院，昆明 650500)
摘 要: 通过热力学分析和实验研究了真空条件下碳热还原氧化铝的二次反应。热力学分析表明：低温、高压有利于碳热还原氧化铝的产物Al2O、Al与CO的二次反应。分别绘制了Al2O和Al在一定分压下，与CO的二次反应平衡曲线图，给出了各二次反应的CO平衡分压与温度的关系，根据CO的分压和温度、利用二次反应平衡曲线图分析二次反应的产物。氧化铝与石墨的真空碳热还原实验研究证实：Al2O与CO降低温度首先生成Al4O4C和C，Al与CO降低温度首先生成Al4O4C和Al4C3，符合根据二次反应平衡曲线图分析得到的结论，说明二次反应平衡曲线图的合理性。
关键字: 碳热还原；氧化铝；石墨；真空；Al2O；Al
（1. National Engineering Laboratory of Vacuum Metallurgy, Faculty of Metallurgy and Energy Engineering,
Kunming University of Science and Technology, Kunming 650093, China;
2. Faculty of Science, Kunming University of Science and Technology, Kunming 650500, China）
Abstract:The back-reactions of the carbothermal reduction of alumina in a vacuum were investigated. The thermodynamic analysis indicates that both low temperature and high pressure favor the back-reactions of Al2O3, Al and CO generated from the carbothermal reduction of alumina. The equilibrium curves for the back-reactions of Al2O and CO, and those of Al and CO are obtained, respectively, for certain partial pressures of Al2O and those of Al, showing the CO equilibrium partial pressure of the back-reactions as a function of the temperature. From the equilibrium curves, the species formed by the back-reactions are determined by the CO partial pressure and the temperature. The experiments on the alumina and graphite show that Al2O reacts back with CO to first form Al4O4C and C, and Al reacts back with CO to first form Al4O4Cand Al4C3, verifying the conclusions obtained from the equilibrium curves. The equilibrium curves of the back-reactions are reasonable.
Key words: carbothermal reduction; alumina; graphite; vacuum; Al2O; Al
