(1. 昆明理工大學(xué) 真空冶金國家工程實驗室，昆明 650093；
2. 昆明理工大學(xué) 云南省有色金屬真空冶金重點實驗室 冶金與能源工程學(xué)院，昆明 650093；
3. 昆明理工大學(xué) 材料科學(xué)與工程學(xué)院，昆明 650093)
摘 要: 采用XRD、氣相色譜儀、EDS及質(zhì)量損失等手段與方法，在不同反應(yīng)溫度、系統(tǒng)壓力、添加劑及反應(yīng)時間對氧化鋁在碳熱及氯化過程進行研究。結(jié)果表明：碳熱與氯化過程生成的氣體主要是CO，含量達98.4%(質(zhì)量分?jǐn)?shù))以上；碳熱過程在50~100 Pa、高于1 693 K時，Al4O4C與Al4C3開始生成，且含量隨著溫度的升高與保溫時間的延長而增加；在1 Pa及1 773 K時，Al4O4C碳熱轉(zhuǎn)化為Al4C3；分別添加10%Fe2O3與10%SiO2(質(zhì)量分?jǐn)?shù))，在40~100 Pa、1 803 K、保溫120~150 min時，可使物料質(zhì)量損失率達到26.70%與30.13%，促進碳熱過程向生成Al4O4C與Al4C3方向進行；溫度高于1 853 K不利于該反應(yīng)的進行；碳熱−氯化過程是Al2O3與Al4O4C、Al4C3及AlCl3共同反應(yīng)生成低價氯化鋁AlCl，氣態(tài)AlCl進入低溫區(qū)歧解得到金屬鋁。
關(guān)鍵字: 氧化鋁；碳熱還原；氯化法；氯化鋁；真空冶金
XU Bao-qiang1, 2, WANG Peng-cheng1, 3, DAI Yong-nian
（1.National Engineering Laboratory of Vacuum Metallurgy, Kunming University of Science and Technology,
Kunming 650093, China;
2. Key Laboratory of Nonferrous Metals Vacuum Metallurgy of Yunnan Province, Faculty of Metallurgy and
Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China;
3. Faculty of Material Science and Engineering, Kunming University of Science and Technology, Kunming 650093, China）
Abstract:Under conditions of different reaction temperatures, system pressures, additives and reaction time, the carbothermic behaviors and chloride behaviors of Al2O3 were investigated by XRD, gas chromatography, EDS and mass loss method. The results show that the gas forming in the process of carbothermic and chloride process is mainly CO, the content of CO reaches over 98.4%. Al4O4C and Al4C3 begin to generate under the conditions of 1 693 K and 50−100 Pa, and their contents increase with increasing temperature and prolonging reaction time. Under 1 Pa and 1 773 K, Al4O4C will transform into Al4C3. The mass loss rate of reactants reaches as high as 26.70% and 30.13% when added 10%Fe2O3 and 10%SiO2, respectively, under the conditions of 1 803 K, 120−150 min, and 40−100 Pa, which means that Fe2O3 and SiO2 can promote the carbothermic processes to generate Al4O4C and Al4C3, but the temperature over 1 853 K is not beneficial to progress the reaction. AlCl gas forms from AlCl3 reacting with Al2O3, Al4O4C and Al4C3 during alumina carbothermic reduction and chloride process, and AlCl gas disproportionates into Al and AlCl3 at low temperatures.
Key words: alumina; carbothermic reduction; chlorination; AlCl; vacuum metallurgy
