Isolating salts of organic acids from fermentation broth, e.g. 2-keto-L-gulonate for production of Vitamin C, involves partial evaporative crystallization followed by displacement precipitation

摘要

A method for isolating salts (I) of organic acids from a fermentation broth involves: (a) partial evaporative crystallization; and (b) displacement precipitation of the salt. Independent claims are also included for the following: (1) a method (M1) for the production of free organic acids from their salts and suitable hydroxides by: (a) dissolving the crystalline salt of an organic acid in water or an aqueous solution; (b) removing multivalent cations from the solution; and (c) liberating the acid from the solution; (2) a method (M2) for the production of esters of organic acids by esterifying acids (obtained as described above) with 1-6C alkanols; and (3) a method for the production of ascorbic acid from 2-keto-L-gulonic acid by formation of the ester (methods M1 and M2) lactonization of the ester and isolation of crude ascorbic acid.