METHOD FOR PURIFYING ISOLEUCINE

摘要

PROBLEM TO BE SOLVED: To provide a method for purifying isoleucine easily, in high yield and purity using an inexpensive precipitant. SOLUTION: This method for purifying isoleucine comprises the following process: p-vinylbenzenesulfonic acid or a water-soluble salt thereof is made to act on an isoleucine-containing aqueous solution to form isoleucine-p- vinylbenzenesulfonic acid salt crystal followed by separating the salt and then decomposing it to purify and obtain the objective isoleucine; wherein the p- vinylbenzenesulfonic acid may be either of free acid form or in the form of alkali metal salt or ammonium salt.