Аминотрис натрия (метиленфосфонат)

Description

Sodium aminotris(methylenephosphonate) is the sodium salt of nitrilotris(methylenephosphonic) acid, known in water treatment under the abbreviation ATMP (ATMP). Class: organophosphonates, complexones. Three phosphonic groups on one nitrogen atom form stable chelates with calcium, magnesium, iron, copper and zinc ions. Commodity forms: aqueous solution and coarse-crystalline granules. Sodium salt is convenient because it does not acidify the system, unlike free acid.

Identification

• CAS No.: 20592-85-2
• Chemical formula: C3H12NO9P3 xNa
• English name: Sodium aminotris(methylenephosphonate)
• EU number: 243-900-0
• UNII: 9HON9B633X
• DSSTox ID: DTXSID4027812
• Catalog section: phosphines (organophosphorus products)
• Synonyms: sodium salt of nitrilotris (methylenephosphonic acid); tris(phosphonomethyl)amine sodium salt; sodium nitrilotrimethylenephosphonate; aminotris (sodium methylenephosphonate); sodium salt of amino(trimethylenephosphonic acid)
• Trade designations: Kublen A 4015; A 2802N; Corylate; Briquette 301 Low AM; Sequence 20Na38

Basic Attributes

• Molecular weight: 307
• Exact weight: 412.90300
• PSA Specs: 241.44
• XLogP3: −3.53 (logarithm)
• Appearance: liquid; coarse granules
• Melting point: 210–215 °C
• Boiling point: 480.0 °C
• Solubility in water: 3.34 M
• Vapor pressure: 6.86 × 10⁻¹² mm Hg. Art.

Operating principle

The molecule carries three −CH2PO3 groups linked to a nitrogen atom. This geometry produces a multi-toothed ligand: it captures hardness and transition metal cations, holding them in solution. Additionally, the effect of substoichiometric inhibition works - a small addition of phosphonate is adsorbed on the nuclei of calcium carbonate crystals and distorts their growth, which is why dense scale does not form even at a reagent concentration much lower than the equivalent one.

Scope of application

• circulating cooling systems of thermal power plants, oil refineries, oil field make-up systems: inhibitor of deposits, primarily calcium carbonate
• corrosion inhibition: gives good results in compositions with zinc salts and phosphates, showing synergy with other additives
• textile production: chelating agent that binds metal ions in dyeing and bleaching baths
• washing and cleaning compositions: complexone, which increases the effectiveness of surfactants in hard water

Benefits of the sodium form

• the solution is close to neutral, which eliminates the need for neutralization during dosing
• in a neutral and slightly acidic environment the composition does not emit an ammonia odor
• resistance to hydrolysis is higher than that of polyphosphates, so the reagent works in hot circuits

Safety Information

• GHS classification: not classified

Storage and handling

The container is tightly closed, the room is dry, protected from freezing when supplied in liquid form. Dosing is carried out using a dosing pump into the make-up or circulation line. When working, use gloves and safety glasses: concentrated solutions of phosphonates irritate the skin and eyes.