A method for the production of reduction cell grade alumina from alkali metal/aluminum chloride complexes comprising the steps of:A. reacting the alkali metal/aluminum chloride complexes with oxygen in a three phase fluidized bed comprising:(I) as a solid phase, particles or pebbles of alumina of at least about 1/16" in average diameter;(II) as a gaseous phase oxygen fed at a rate to provide a fluidizing gas velocity above about 8'/sec.; and(III) as a liquid phase coating the particles of alumina an alkali metal/aluminum chloride complexes; andB. separating the product solids from the gases exiting the fluidized bed.