高温素材プロセッシング・新材料

[3108-09-01] 高温熱炭素還元によるアルミナオキシカーバイドの作製

^○シャハトウ アミナ¹、ビニョブ ラビ¹、曾 理浩雯¹、伊高 健治¹ (1. 弘前大学)

司会: 邑瀬邦明（京都大学）

キーワード：熱炭素還元、アルミニウムカーバイド、アルミニウムオキシカーバイド、アルミナ

Up to now, the industrial production of aluminum was manufactured via the Hall-Héroult method combining dissolving alumina (Al2O3) in fused cryolite (NaF-AlF3) with an electrolysis process.
Although this method is free from severe problems such as high greenhouse gas and perfluorocarbon emission, there is drawbacks of high energy consumption (0.186 GJ/kg Al). Therefore, to surpass these problems, alternatives methods were developed such as the carbothermic reduction of Al2O3 which shows a significant decrease in terms of CO2 emission and energy consumption.
In our previous work, we have successfully to produce aluminum via direct reduction of alumina by carbon in an induction furnace, however a very low reduction yield of 5% was achieved because of semi-reduced by- product such as two phases of aluminum oxycarbides, Al2OC and Al4O4C or as aluminum carbide, Al4C3.
In this research work, we investigated the effect of heating time variation on the time-line production of both phases of aluminum oxycarbides.
The result shows that Al4O4C was the product formed in heating time of 15 min at maximum temperature of 1500°C which make sense due to less interaction between alumina and carbon particles because of short time, while, the amount of Al4O4C started to increase with increasing heating time to 30, 45 and 60 min.
n this heating condition, the gas-phase loss of aluminum element was almost suppressed.