(1. 昆明理工大学 省部共建复杂有色金属资源清洁利用国家重点实验室，昆明 650093；
2. 昆明理工大学 真空冶金国家工程实验室，昆明 650093；
3. 云南省有色金属真空冶金重点实验室，昆明 650093；
4. 昆明理工大学 冶金与能源工程学院，昆明 650093)
摘 要: 针对真空碳热还原法炼镁过程镁蒸气发生逆反应这一关键问题，研究了真空条件下CO2/CO分别对镁蒸气冷凝的影响，以期为该过程中镁蒸气的安全高效冷凝并收集提供理论依据。结果表明：30 Pa下镁蒸气的冷凝是直接由气态变为固态的凝华过程；在系统压强30 Pa、加热温度700~800 ℃保温30 min的条件下，CO2会使冷凝物表面结晶形貌不平整，但不会与镁蒸气发生化学反应；在相同实验条件下，CO会与镁发生化学反应，所得到的冷凝物含镁、氧、碳元素，这阻碍镁蒸气冷凝成形貌规则的晶体。
关键字: 镁蒸气；CO；CO2；真空；冷凝
（1. State Key Laboratory of Complex Non-ferrous Metal Resources Clear Utilization, Kunming University of Science and Technology, Kunming 650093, China;
2. National Engineering Laboratory for Vacuum Metallurgy, Kunming University of Science and Technology, Kunming 650093, China;
3. Key Laboratory of Vacuum Metallurgy for Nonferrous Metal of Yunnan Province, Kunming 650093, China;
4. School of Metallurgy and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China）
Abstract:Aiming at the key problem of reverse reaction of magnesium vapor in vacuum carbothermal reduction method, the effects of CO2/CO on magnesium vapor condensation under vacuum conditions were studied, which is to provide theoretical basis for safe and efficient condensation and collection of magnesium vapor in the process. The results show that the condensation of magnesium vapor is a desublimation process from gas to solid at 30 Pa. In addition, when the system pressure is 30 Pa, the heating temperature is 700-800 ℃ and is kept for 30 min, CO2 can make the crystalline morphology of the condensate uneven, but cannot react with magnesium vapor. And under the same experimental conditions, CO can chemically react with magnesium. The obtained condensate contains magnesium, oxygen and carbon. CO can hinder the magnesium vapor to condensate into the regular crystal.
Key words: magnesium vapor; CO; CO2; vacuum; condensation
