Process for producing high-purity α-alumina
AssigneeNippon Light Metal Company, Ltd.
InventorsJun Mizuno, Toshihiro Matsuba, Shigeo Yamamoto, Takashi Yamada
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Abstract
Provided is a process for producing a high-purity α-alumina in which an Si content, an Fe content, a Ca content, and an Na content are simultaneously removed. The high-purity α-alumina is produced by burning aluminum hydroxide having an Na content of 0.11 mass % or less, an Fe content of 6 ppm or less, a Ca content of 1.5 ppm or less, and an Si content of 10 ppm or less as impurities in terms of alumina respectively, and having an average particle diameter of 55 μm or less at a burning temperature of 1,100 to 1,500° C. by using a burning vessel containing Al2O3 in a range of 85 to 93 wt % and SiO2 in a range of 7 to 14 wt % and subjecting the obtained α-alumina to wash treatment.
Claims7
A process for producing a high-purity α-alumina, comprising:
- burning aluminum hydroxide having an Na content of 0.11 mass % or less, an Fe content of 6 ppm or less, a Ca content of 1.5 ppm or less, and an Si content of 10 ppm or less as impurities in terms of alumina respectively, and having an average particle diameter of 55 μm or less at a burning temperature of 1,100 to 1,500° C. by using a burning vessel containing Al2O3 in a range of 85 to 93 wt % and SiO2 in a range of 7 to 14 wt %;
- and
- subjecting the obtained α-alumina to wash treatment.
Dependencies are inferred from the claim text.