METHOD OF PRODUCING SPHEROID-SHAPED ALUMINIUM OXIDE GRANULES Russian patent published in 1997 - IPC

FIELD: non-ferrous metallurgy. SUBSTANCE: oxygen-containing aluminium compounds of formula Al₂O₃•nH₂O, wherein 0.25<n<2.9, are mixed up with aluminium trihydroxide compounds containing 10-90 wt.% aluminium. Resulting mixture is subjected to mechanical-chemical activation by exposing powder particles to chock effect. Powder particles subjected to treatment collide against each other or against components of disintegrator rotors at speed 80-200 m/s, collision number being at least 2. Mixture is fed into plate-type granulator, mixed up therein with water and shaped into spherical 2-6 mm dia. granules. Freshly shaped granules are held in saturated water steam at temperature 25-100 C for 1-5 h, followed by subjecting granules to drying and calcination at 350-500 C in air flow, nitrogen flow or in flow of smoke gases, volume velocity of latter being 500-5000 h^-1 for 1-5 h. EFFECT: method permits to produce high-purity spheroidal granules of aluminium oxide having developed specific surface area and resistant to moisture in form of droplets. 5 cl, 2 tbl