RECOVERY OF CARBOXYLIC ACID FROM THEIR MAGNESIUM SALTS BY PRECIPITATION USING HYDROCHLORIC ACID, USEFUL FOR FERMENTATION BROTH WORK-UP

摘要

The invention provides a method for preparing a carboxylic acid, which method comprises the steps of- providing magnesium carboxylate, wherein the carboxylic acid corresponding with the carboxylate has a solubility in water at 20 °C of 80 g/100 g water or less;- acidifying the magnesium carboxylate with HCl, thereby obtaining a solution comprising carboxylic acid and magnesium chloride (MgCl₂);- optionally a concentration step, wherein the solution comprising carboxylic acid and MgCl₂ is concentrated;- precipitating the carboxylic acid from the solution comprising the carboxylic acid and MgCl₂, thereby obtaining a carboxylic acid precipitate and a MgCl₂ solution.;The inventors found that the addition of HCl to a magnesium salt of the carboxylic acid and subsequent precipitation of the carboxylic acid from the solution leads to a very efficient separation of the carboxylic acid from a magnesium carboxylate solution.