Patent ID: 7005531

Claim:
Method of making alkali iron(III)gluconate complex, comprising the following steps: (i) mixing a water soluble iron(III)salt in aqueous solution, simultaneously or in any desired sequence, with a member selected from the group consisting of gluconic acid, a water soluble salt of gluconic acid and combinations thereof, and a member selected from the group consisting of an alkali hydroxide, an alkali carbonate, an alkali hydrogen carbonate and combinations thereof, so that the reaction mixture has an acid value (pH-value) within the range of from 7.0 to 12, provided that when alkali hydroxide is used, gluconic acid or a water soluble salt of gluconic acid is provided at the beginning of the reaction or is added to the reaction mixture simultaneously with the alkali hydroxide; (ii) heating the reaction mixture until the alkali iron(III)gluconate complex has formed; and (iii) adding an organic solvent which is miscible with water until the alkali iron(III)gluconate complex is precipitated.