Patent ID: 7837961

Claim:
A process for extracting aluminum ions from a mixture comprising iron ions and the aluminum ions, said process comprising recovering said aluminum ions from a composition comprising said aluminum ions, said iron ions, an acid, an organic solvent and an extracting agent adapted to form an organometallic complex substantially selectively with said iron ions or with said aluminum ions, said extracting agent being soluble in said organic solvent, wherein when said extracting agent is adapted to form an organometallic complex substantially selectively with said iron ions, said composition comprises an acidic aqueous phase comprising said aluminum ions and said acid, and an organic phase comprising said organic solvent and said iron ions complexed with said extracting agent, said aluminum ions are recovered by separating said aqueous phase from said organic phase by means of a hollow fiber membrane, and reacting said separated aqueous phase with a base, and wherein when said extracting agent is adapted to form an organometallic complex substantially selectively with said aluminum ions, said composition comprises an acidic aqueous phase comprising said iron ions and said acid, and an organic phase comprising said organic solvent and said aluminum ions complexed with said extracting agent, said aluminum ions are recovered by separating said aqueous phase from said organic phase by means of a hollow fiber membrane, reacting said separated organic phase with an acid so as to obtain another aqueous phase comprising said aluminum ions and another organic phase, separating said another aqueous phase from said another organic phase and recovering said aluminum ions in the form of Al(OH) 3 by reacting said another aqueous phase with a base.