| 摘要 |
<p>The invention relates to methods for producing aluminium oxides, inter alia corundum, of high chemical purity (not less than 99.99 wt%). High-purity corundum is used to produce leuco-sapphire, which in turn has a broad range of application, for example in the manufacture of substrates for microcircuits, light-emitting diodes and laser diodes, and in implants and artificial joints, micro scalpels, protective glazings, jewellery, etc. High-purity corundum can be used for manufacturing refractory products for use in the production of ultra-pure materials. Porous and high-purity materials based on aluminium oxides are widely applicable in such fields as the production of catalysts and sorbents. The aim of the proposed method is to produce corundum of high chemical purity (not less than 99.99 wt%). The essence of the method is that high-purity corundum is produced from aluminium powders and water by progressive heat treatment of boehmite, obtained by hydrothermal oxidation of powdered aluminium. The above-mentioned aim is achieved by implementation of the proposed method, which involves water treatment and the metered feeding of water and aluminium into a mixer, the heating of a high-pressure reactor to a working temperature, the controlled feeding of a suspension of powdered aluminium in water from the mixer into the high-pressure reactor using a controllable high-pressure pump, the atomization of the suspension in the reactor using atomizing nozzles, the separation of a water-hydrogen mixture from the boehmite and the subsequent execution of further process operations related to the separation of boehmite and the heat treatment thereof under specified temperature regimes and time parameters.</p> |
