Patent ID: 8658831

Claim:
A method for separating a primary amine being an N,N-dialkylbisaminoalkylether, from mixtures comprising said primary amine and at least one of a secondary amine being an N,N,N′-trialkylbisaminoalkylether and a tertiary amine being an N,N,N′,N′-tetraalkylbisaminoalkylether, the method comprising the steps: (α) joining said mixture and at least one of a ketone and an aldehyde, wherein said at least one of a ketone and an aldehyde forms an azeotrope with water, for reacting said primary amine with said at least one of a ketone and an aldehyde, thereby providing a primary amine based imine by a Schiff base reaction; (β) separating the primary amine based imine from said at least one of the secondary or tertiary amine by distillation; (γ) recovering the primary amine from its primary amine based imine by hydrolysis of the primary amine based imine; and (δ) after recovering the primary amine from its primary amine based imine, removing the at least one ketone or aldehyde from the primary amine and water by azeotrope distillation.