Patent ID: 8277615
Filing Date: 2012-10-02
Classification: B01D,C07C,C07D,C07F

Abstract:
1. A method for separating mixtures of substances using one or more ionic liquids and/or polymers as a selective additive, wherein the one or more ionic liquids and/or polymers are freed from one or more volatile components by multistage rectification in a distillation unit, wherein (i) at least one volatile auxiliary is used; (ii) the at least one volatile auxiliary used in the bottom of the distillation unit contributes a significant proportion of at least 50% to the pressure owing to its partial pressure; (iii) the pressure in the bottom of the distillation unit minus the partial pressure of the at least one volatile auxiliary which prevails there does not exceed 10 mbar; (iv) the at least one volatile auxiliary used leaves the distillation unit for the most part together with the ionic liquids and/or polymers at the bottom; (v) the at least one volatile auxiliary has a partition coefficient which is higher than that of the ionic liquids and/or polymers but lower than the partition coefficient of the one or more volatile components; and (vi) the auxiliary is reused together with the one or more ionic liquids and/or polymers and is substantially circulated without removing the auxiliary.