Patent ID: 6667417
Filing Date: 2003-12-23
Classification: C07C,C12P

Abstract:
A process for producing lactic acid from a medium resulting from a fermentation of one carbohydrate, said medium containing an alkaline earth-metal salt of lactic acid, comprising:(a) converting said alkaline earth-metal salt of lactic acid into a water soluble alkali metal lactate salt by reacting said medium with a conjugated base of an alkali metal from a subsequent step to form said water soluble alkali metal lactate salt and a basic compound of said alkaline earth metal; (b) separating said water soluble alkali metal lactate salt and said basic compound of said alkaline earth metal; (c) splitting said water soluble alkali metal lactate to form a conjugated alkali metal base and a lactic acid product; (d) separating said conjugated alkali metal base and said lactic acid product; (e) re-using said separated conjugated alkali metal base to provide the conjugated base of an alkali metal in step (a); and, (f) reusing said basic compound of said alkaline earth metal, separated in step (b), to provide a neutralizing agent to form an alkaline earth-metal salt of lactic acid-containing medium for reaction according to step (a).