PROCEDEU DE OBTINERE A ALUMINEI SFEROIDALE

摘要

1535807 Spheroidal alumina particles UOP Inc 15 April 1976 [16 April 1975] 15489/76 Heading C1A Spheroidal alumina particles are made by (a) mixing alumina powder, an aluminium salt of a strong acid, a water-soluble surfactant and sufficient water to yield an extrudable mixture; (b) stirring or mulling (i.e. mixing or grinding) the mixture until the decreasing viscosity stabilizes, and extruding the mixture; (c) segmenting and balling the extrudate by centrifugal force on a spinning drum; (d) drying and calcining the resulting spheroidal product. The aluminium salt may be the nitrate, chloride or sulphate. Preferably, calcining is effected for 1-4 hours at 525-775‹ C. in air containing 1-5 wt. per cent steam and then for 1-4 hours at 875-1100‹ C. in air. The product provides a thermally-stable catalyst base.