Ethylene Diamine Tetra (Methylene Phosphonic Acid) Sodium/EDTMPS
Other names: Sodium ethylenediaminetetramethylenephosphonate, Sodium ethylenediaminetetramethylenephosphonate
Molecular formula: C6H15O12N2P4Na5
Relative molecular mass: 546.03
I. Performance and Applications
EDTMPS is a nitrogen-containing organic polyphosphonic acid, belonging to the cathodic corrosion inhibitor category. Compared with inorganic polyphosphates, its corrosion inhibition rate is 3-5 times higher. It is miscible with water, non-toxic and non-polluting, with good chemical stability and temperature resistance, maintaining good scale inhibition effect even at 200℃. EDTMPS dissociates into 8 positive and negative ions in aqueous solution, thus chelating with multiple metal ions to form multiple monomeric macromolecular network complexes, loosely dispersed in water, disrupting the normal crystallization of calcium scale. EDTMPS has good scale inhibition effect on calcium sulfate and barium sulfate scale.
EDTMPS is used as a corrosion and scale inhibitor in circulating water and boiler water, a complexing agent in cyanide-free electroplating, a chelating agent in the textile printing and dyeing industry, and an oxygen bleaching stabilizer.
II. Technical Specifications
| Item |
Indicator |
| Appearance |
Amber-colored transparent liquid |
| Active ingredient (as EDTMPA),% |
24.0～26.0 |
| Active ingredient (as EDTMPS),% |
30.0～32.6 |
| Chloride (as Cl-), % |
≤2.0 |
| pH (stock solution) |
6.0～8.0 |
| Density (20℃), g/cm3 |
≥1.25 |
| Fe content(as Fe), mg/L |
≤10.0 |
III. Usage Method
When added alone to circulating cooling water, the general dosage is 2-10 mg/L. EDTMPS mixed with HPMA at a 1:3 ratio can be used for boiler water treatment in low-pressure boilers. EDTMPS can also be used in combination with BTA, PAAS, zinc salts, etc.
IV. Packaging and Storage
EDTMPS is packaged in plastic drums, 25kg per drum, or as required by the user. Store in a cool, dark place indoors. Shelf life is six months.
V. Safety Precautions
EDTMPS is neutral. Take precautions during handling to avoid contact with skin and eyes. If contact occurs, rinse immediately with plenty of water.
