Diethylenetriaminepenta(methylene-phosphonic acid) (DTPMPA) CAS No.: 15827-60-8
Diethylenetriaminepenta(methylene-phosphonic acid) (DTPMPA, CAS 15827-60-8) is an organophosphonic acid chelating agent characterized by multiple phosphonate groups that confer strong metal-ion sequestration and excellent thermal stability (effective above 210°C) . Its primary industrial role is as a scale and corrosion inhibitor, particularly in circulating cooling water systems, boiler water treatment, and oilfield injection water with high barium carbonate concentrations, where it effectively suppresses carbonate and sulfate scale formation . It is typically supplied as a brownish, acidic aqueous solution and also finds secondary applications as a peroxide stabilizer, chelating agent in textiles, and pigment dispersant .
1. Overview
DTPMPA is an organophosphonate supplied as a brown to pale yellow transparent liquid (typically 50% active solution). It is a highly effective chelating agent, scale inhibitor, and corrosion inhibitor with excellent thermal stability (effective above 210°C), making it ideal for demanding industrial water treatment applications .
2. Key Features
Excellent scale inhibition – controls CaCO₃, CaSO₄, BaSO₄ scales
Superior thermal stability – effective at high temperatures (>210°C)
Strong chelation – forms stable complexes with Fe, Ca, Mg, Ba ions
Alkaline-friendly – works without pH adjustment in cooling systems
Peroxide stabilizer – prevents decomposition in bleaching processes
Low toxicity – safer than many alternative industrial chemicals
3. Key Specifications (50% Active Grade)
| Parameter | Typical Value | Explanation |
|---|---|---|
| Appearance | Brown to amber clear liquid | Color may vary by concentration |
| Active Content | 48.0 – 52.0% | Core performance indicator |
| Density (20°C) | 1.35 – 1.45 g/mL | Affects volume dosing |
| pH (1% solution) | ≤ 2.0 | Highly acidic |
| Phosphorous Acid | ≤ 3.0% | Impurity indicator |
| Chlorides (Cl⁻) | 12 – 17% | Byproduct from manufacturing |
| Iron (Fe) | ≤ 35 ppm | Low iron prevents discoloration |
| Molecular Weight | 573.20 g/mol | For stoichiometric calculations |
4. Applications
| Area | Specific Uses |
|---|---|
| Water Treatment | Scale/corrosion inhibitor in cooling towers, boilers, oilfield injection (especially effective for BaSO₄ scale) |
| Textile Industry | Peroxide stabilizer in bleaching; chelating agent for hard ions |
| Pulp & Paper | Oxygen delignification stabilizer; pigment dispersant |
| Industrial Cleaning | Component in metal cleaning and descaling formulations |
| Agriculture | Micronutrient chelator (carries Fe, Zn, Mn to plants) |
| Cosmetics | Stabilizer and chelator in personal care products |
| Construction | Concrete additive for improved properties |
5. Grade/Product Forms
| Form | Active Content | Typical Use |
|---|---|---|
| Standard Solution | 50% | General water treatment, industrial applications |
| Concentrated Solution | 60%+ | Heavy-duty scale control, custom blending |
| Solid/Powder | ≥95% | Research, specialized formulations (store at -20°C) |
6. Buying Guide
Select by application:
Cooling water/boiler treatment → Standard 50% solution
Oilfield (BaSO₄ scale) → DTPMPA is specifically recommended
Peroxide stabilization → Standard grade, verify active content
Quality verification:
Request CoA confirming active content (≥50%), phosphorous acid (≤3%), and iron (≤35 ppm)
Check appearance – should be clear, not turbid
Storage & handling:
Store in plastic/HDPE containers (not metal – corrosive)
Keep in cool, indoor area (away from direct sunlight)
Shelf life: 10–12 months
Corrosive – use PPE (gloves, goggles)
Regulatory compliance:
Meets Chinese standard HG/T 3777-2023
Check local phosphate regulations before use
7. FAQ
Q: What is DTPMPA used for in water treatment?
A: It prevents scale (CaCO₃, CaSO₄, BaSO₄) and corrosion in cooling towers, boilers, and oilfield water injection systems. It works well in alkaline conditions without pH adjustment .
Q: How does DTPMPA compare to other phosphonates (ATMP, HEDP)?
A: DTPMPA has better thermal stability (>210°C) and is more effective against barium sulfate scale. For high-temperature applications or oilfield use, DTPMPA is preferred .
Q: Is DTPMPA hazardous?
A: Yes – corrosive. GHS: H314 (severe skin burns/eye damage), H318 (serious eye damage). Use full PPE .
Q: What is the typical dosage for water treatment?
A: Scale inhibition: 1–30 mg/L; Cleaning formulations: 1000–2000 mg/L .
Q: Can DTPMPA be used with other chemicals?
A: Yes – often combined with polycarboxylates for enhanced performance. Avoid strong oxidizers.
8. Delivery & Service
Packaging: 25kg or 250kg plastic drums; 1000kg IBC; bulk isotanks
Lead time: Stock: 3–7 days; bulk orders: 2–3 weeks
Documentation: CoA, MSDS, TDS
Certifications: ISO 9001 (varies by supplier)
Shipping: Corrosive liquid (UN 3265 / Class 8) – requires hazardous documentation
