POLYALKYLENE POLYAMINE POLYMETHYLPHOSPHONIC ACID SYNTHESIS METHOD Russian patent published in 2011 - IPC C07F9/38 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing polyalkylene polyamine polymethylphosphonic acids used as mineral salt deposit inhibitors in heating systems, hot water supply systems and water collection systems of industrial plants. The method involves obtaining polyalkylene polyamine polymethylphosphonic acids, selected from nitrilotrimethylphosphonic acid, methyliminodimethylphosphonic acid, ethylenediamine tetramethylphosphonic acid, hexamethylene diamine tetramethylphosphonic acid, diethylene triamine pentamethylphosphonic acid and triethylene tetraamine hexamethylphosphonic acid, by reacting the corresponding amine or corresponding ammonium compounds with formaldehyde and phosphorous acid in a chloride solution while boiling and then cooling the reaction mass and extracting the end product in solid form, wherein formaldehyde (in form of formalin) is used in 5-7% excess compared to stoichiometry, and the reaction process is carried out at defined conditions for adding starting reagents, where phosphorus acid, hydrochloric acid and formalin are added first, and the corresponding amine or ammonium compound is then added to the formed reaction mixture while stirring for 3-5 minutes.

EFFECT: method simplifies the technique, reduces power consumption, widens the range and increases output of polyalkylene polyamine polymethylphosphonic acids.

3 cl, 8 ex