Patent ID: 6982026

Claim:
An azeotropic distillation process for the recovery of at least one of an organic acid or an organic acid amide from a feed stream comprising at least one of the organic acid or the organic acid amide, comprising the steps of: mixing at least one azeotroping agent and a feed stream that comprises at least one of an organic acid or an organic acid amide and water, wherein the organic acid is selected from the group consisting of monocarboxylic acids, dicarboxylic acids, and tricarboxylic acids having from 2 to 8 carbon atoms, and the organic acid amide is selected from the group consisting of amides of monocarboxylic acids, dicarboxylic acids, and tricarboxylic acids having from 2 to 8 carbon atoms; and distilling the mixture comprising the at least one azeotroping agent and the feed stream by a method comprising the steps of (i) heating the mixture, wherein the heating is sufficient to produce a first vapor stream that comprises water and at least one first heteroazeotrope comprising (a) the organic acid or the organic acid amide and (b) the at least one azeotroping agent; and (ii) separating the first vapor stream from the mixture and producing a first bottoms stream, wherein the first bottoms stream comprises at least some of the organic acid or the organic acid amide, wherein the first bottoms stream is capable of being separated into a first phase and a second phase, wherein the first phase comprises a higher concentration of the organic acid or the organic acid amide than the second phase, and wherein the second phase comprises the at least one azeotroping agent; separating the first bottoms stream into a first phase and a second phase; condensing the first vapor stream to produce a first liquid stream; distilling the first liquid stream by a method comprising the steps of (A) adjusting the temperature of the first liquid stream to a temperature sufficient to produce a second vapor stream that comprises an azeotrope that comprises water and the at least one azeotroping agent and a second bottoms stream; (B) separating the second vapor stream from the second bottoms stream, wherein the second bottoms stream comprises at least some of the organic acid or the organic acid amide.