Calcium, magnesium or strontium citric acid salts prodn. - by heating the corresp. salts of aconitic acid, iso-citric acid or allo-iso-citric acid in aq. medium with alkali(ne earth) hydroxide(s)

摘要

Mg- and/or Sr salts of citric acid are made by reacting the corresponding salt(s) of cis- or trans-aconitic acid isocitric acid, alloisocitric acid and/or mixts. of these, with Ca(OH)2, Mg(OH)2 and/or Sr(OH)2. The reaction is carried out in aq. medium at >=160 degrees C, esp. 160-300 degrees C. High conversion of the unsaturated dicarboxylic acids to the desired citric acid salt is provided.