METHOD FOR PURIFYING AMINOPHOSPHONIC ACID

摘要

PROBLEM TO BE SOLVED: To obtain aminophosphonic acid with an extremely low content of impurities such as hydrogen chloride, carbonyl compounds and phosphonic acid. SOLUTION: This method for purifying the aminophosphonic acid is characterized by mixing an aqueous solution containing the aminophosphonic acid with at least one kind selected from the group consisting of a <=3C alcohol, acetone and tetrahydrofuran, precipitating the aminophosphonic acid and separating the aminophosphonic acid.