ALUMINA PRODUCTION PROCESS

摘要

An improved process for producing alumina from bauxite is disclosed comprising the steps of: a) wet grinding of the bauxite in the presence of an agent capable of reducing the viscosity of the semiliquid paste obtained; b) caustic etching of the bauxite ground in step a) with a concentrated solution of sodium hydroxide until a liquid phase is obtained comprising aluminium hydroxide and a solid phase; c) removal of the solid phase formed in step b) from the liquid phase; d) precipitation of the aluminium hydroxide from the liquid phase of step c); e) filtration of the aluminium hydroxide precipitated in step d); and f) calcination of the aluminium hydroxide of step e).