Process for the production of an alumina product which is free from iron, silicon and titanium from materials containing aluminium

摘要

Process for the removal of iron and titanium minerals from materials containing aluminium in at least one chlorination stage through the use of an excess of aluminium trichloride as at least the principal chlorinating agent for the iron and titanium minerals contained, condensing the excess aluminium trichloride to recover aluminium trichloride in impure form, and recycling the impure aluminium trichloride to the chlorination stage together with additional aluminium trichloride or quantities of substoichiometric chlorine feed, or, alternatively, additional quantities of aluminium trichloride and quantities of substoichiometric chlorine feed.