Selective extraction of 2-keto-L-gulonic acid from polar solution, especially reaction mixture obtained in preparing ascorbic acid by lactonization, using mixture of tertiary amine and polar organic diluent

摘要

2-Keto-L-gulonic acid (KGA) is extracted from a polar solvent, by contacting the solvent with an extractant (E1) comprising a tertiary amine (I) and a polar organic diluent (II) in a mixing region. 2-Keto-L-gulonic acid (KGA) is extracted from a (preferably aqueous) polar solvent, by contacting the solvent with a first extractant (E1) comprising a tertiary amine of formula NR1R2R3 (I) and a polar organic diluent (II) in a mixing region. R1 - R3 = 6-14C (preferably 8-12C) alkyl. An Independent claim is also included for the production of ascorbic acid (AA), by at least partially lactonizing KGA, extracting KGA from the obtained AA/KGA mixture by the above method and isolating AA from the residual solution.