Technology for High Pure Aluminum Oxide Production from Aluminum Scrap

3rd Annual International Workshop on Materials Science and Engineering

Ambaryan, G.N.^1 ; Vlaskin, M.S.^1 ; Shkolnikov, E.I.^1 ; Zhuk, A.Z.^1

Joint Institute for High Temperatures, Russian Academy of Sciences, Izhorskaya 13 Bldg 2, Moscow

125412, Russia^1

关键词: Alumina production;    Experimental conditions;    High purity aluminum;    Industrial manufacturers;    Oxidation reactions;    Synergistic effect;    Synthesis process;    Synthetic sapphire;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/250/1/012044/pdf
DOI  :  10.1088/1757-899X/250/1/012044

来源: IOP

【 摘 要 】

In this study a simple ecologically benign technology of high purity alumina production is presented. The synthesis process consists of three steps) oxidation of aluminum in water at temperature of 90 °C) calcinations of Al hydroxide in atmosphere at 1100 °C) high temperature vacuum processing of aluminum alpha oxide at 1750 °C. Oxidation of aluminum scrap was carried out under intensive mixing in water with small addition of KOH as a catalyst. It was shown that under implemented experimental conditions alkali was continuously regenerated during oxidation reaction and synergistic effect of low content alkali aqueous solution and intensive mixing worked. The product of oxidation of aluminum scrap is the powder of Al(OH)3. Then it can be preliminary granulated or directly subjected to thermal treatment deleting the impurities from the product (aluminum oxide). It was shown the possibility to produce the high-purity aluminum oxide of 5N grade (99.999 %). Aluminum oxide, synthesized by means of the proposed method, meets the requirements of industrial manufacturers of synthetic sapphire (aluminum oxide monocrystals). Obtained high pure aluminum oxide can be also used for the manufacture of implants, artificial joints, microscalpels, high-purity ceramics and other refractory shapes for manufacture of ultra-pure products.