CAS No. 6419-19-8 Alias: Aminotrimethylenephosphonic Acid, ATMPA, Nitrilotrimethylenetriphosphonic Acid, Nitrilotrimethylenephosphoric Acid Molecular Formula: N(CH2PO3H2)3 Relative Molecular Mass: 299.05 Structural Formula: I. Properties and Applications ATMP has excellent chelating, threshold inhibition, and lattice distortion effects. It can prevent the formation of scale from scale-forming salts in water, particularly calcium carbonate scale. ATMP is chemically stable in water and not easily hydrolyzed. At higher concentrations in water, it provides good corrosion inhibition. ATMP is used in circulating cooling water systems in thermal power plants and refineries, as well as in oilfield water injection systems. It helps reduce corrosion and scaling in metal equipment or pipelines. In industries such as textile printing and dyeing, ATMP is used as a metal ion chelating agent and can also serve as a metal surface treatment agent. ATMP solid is a crystalline powder, highly soluble in water, hygroscopic, and easy to transport and use, making it particularly suitable for use in cold winter regions. II. Technical Specifications Item | Specification | Complies with HG/T 2841-1997 | Complies with HG/T2841-2005 | | Appearance | Colorless or light yellow transparent liquid | White crystalline powder | Active Component (as ATMP) % ≥ | 50.0 | 50.0 | 95.0 | Aminotrimethylene Phosphonic Acid Content % ≥ | —— | 40.0 | 88.0 | Phosphite (as PO33-) % ≤ | 5.0 | 3.5 | —— | Phosphate (as PO43-) % ≤ | 1.0 | 0.8 | 0.8 | Chloride (as Cl-) % ≤ | 3.5 | 2.0 | 1.0 | Iron (as Fe2+) Content mg/L ≤ | —— | 20.0 | 20.0 | Density (20℃) g/cm3≥ | 1.28 | 1.30 | —— | pH (1% Aqueous Solution) | 1.5-2.5 | 1.5-2.5 | 2.0 |
III. Usage Method ATMP is often compounded with other organic phosphonic acids, polycarboxylic acids, or their salts to form organic water treatment agents for use in circulating cooling water systems under various water quality conditions. The recommended dosage is 1–20 mg/L; when used as a corrosion inhibitor, the dosage is 20–60 mg/L. IV. Packaging and Storage ATMP liquid is packaged in plastic drums, each containing 30 kg or 250 kg; ATMP solid is packaged in plastic woven bags lined with polyethylene bags, each bag net weight 25 kg, or as required by the customer. Store in a cool, ventilated indoor area, protect from moisture and direct sunlight. Shelf life is ten months. V. Safety Precautions ATMP is acidic. Pay attention to labor protection during operation. Avoid contact with skin and eyes. In case of contact, rinse immediately with plenty of water. |