摘要 |
An improved method for the manufacture of phosphonoalkyl iminodiacetic acid (PAIDA) is disclosed. The iminodiacetic acid starting material is reacted with a considerable amount, in excess of stoichiometric requirements, of phosphorous acid to thereby yield a reaction medium insoluble reaction product which can be separated from the reaction medium. In a particularly preferred approach, the phosphorous acid is prepared in situ starting from liquid P4O6. |