Sodium Tripolyphosphate (STPP)
Sodium Tripolyphosphate (STPP), with the chemical formula Na₅P₃O₁₀, is a white, crystalline inorganic compound that has become indispensable across numerous industries.
This multifunctional phosphate salt serves as one of the most widely used additives in commercial and industrial applications worldwide.
Key Properties
STPP is highly soluble in water and exhibits exceptional chelating abilities, meaning it can bind to metal ions like calcium and magnesium.
This property makes it particularly effective in water softening and preventing mineral scale formation.
The compound is non-toxic at approved usage levels and breaks down into harmless phosphates in the environment.
Primary Applications
- Detergents and Cleaning Products: STPP’s most prominent use is as a builder in powdered laundry detergents, where it softens water, enhances surfactant performance, and prevents soil redeposition on fabrics. It maintains cleaning effectiveness even in hard water conditions.
- Food Industry: As a food-grade additive (E451), STPP functions as a preservative and moisture retention agent in seafood, poultry, and processed meats. It helps maintain texture, reduces cooking losses, and extends shelf life while meeting strict food safety standards.
- Industrial Applications: The compound serves critical roles in ceramic production, water treatment, metal surface treatment, and as a dispersing agent in various manufacturing processes.
Available Forms
Sodium Tripolyphosphate is typically supplied as a white powder or granules, available in both technical grade for industrial use and food grade for culinary applications.
It’s packaged in moisture-resistant bags or containers to maintain its stability and effectiveness.
Sodium Tripolyphosphate (STPP)
| Item | Specification |
|---|---|
| Product Name | Sodium Tripolyphosphate |
| CAS Index Name | Triphosphoric Acid, Pentasodium Salt |
| Chemical Formula | Na₅P₃O₁₀ |
| Molecular Weight | 367.86 g/mol |
| Packing | 25 kg / 50 lb plastic bags; 1,000 kg or 2,000 lb jumbo sacks |
| Grade | Technical Grade; High Phase I; Food Grade |
Applications:
| Dishwash Detergents | Softens water, suspends soil, and serves as an anti-spotting agent. |
| Laundry Detergents | Powerful detergent builder for all types of laundry powder. |
| Industrial Cleaners | Sequestrant and dispersant for various cleaners. |
| Ceramic Manufacture | Clay dispersant. |
| Paints | Pigment dispersant. |
| Water Treatment | Scale/corrosion inhibitor and sequestrant |
| Textile processing | Hard water sequestrant |
| Paper manufacture | Coating dispersant |
| Cement manufacture | Mineral dispersant |