Straitmark Holding Ag

David Lemin

Patrick Pierre Notté

Samuel Corentin Cogels

Cedric Nicolas Pirard

Patrick Notté

Cédric Nicolas Pirard

An improved method for the manufacture of phosphonoalkyl iminodiacetic acid MPO&#x2014;X&#x2014;N&#x2014;(CHCOOM)wherein X is a Clinear or branched alkyl group; and M is selected from hydrogen, alkali, earth-alkali, ammonium and protonated amine is disclosed. The iminodiacetic acid starting material is reacted with a substantially stoichiometric amount of phosphorous acid, in the presence of a large excess of phosphoric acid to thereby yield a reaction medium insoluble reaction product (PAI-DA) which can be separated from the reaction medium. In a particularly preferred approach, the phosphorous acid is prepared in situ starting from liquid PO.

Method for the manufacture of phosphonoalkyl iminodiacetic acid

The technology of this invention concerns a method for the manufacture of hydroxy diphosphonic acids containing an amino moiety. The method specifically involves reacting a liquid POwith an aminocarboxylic acid in the presence of a sulfonic acid. The aminocarboxylic acid is selected from 3 structurally different compounds. The amino hydroxy diphosphonic acids can be synthesized with high selectivity and purity and the unreacted starting raw materials can easily and conveniently be recirculated.

Growing community of inventors

Brussels, Belgium

David Lemin