Sodium tripolyphosphate

Sodium tripolyphosphate (CAS 7758-29-4), commonly known as STPP or E451i, is a polyphosphate salt used across detergent manufacturing, food processing, and industrial treatment applications. It functions primarily as a sequestrant, builder, and dispersing agent, binding calcium and magnesium ions to improve process efficiency and product performance across various sectors.

In detergent and cleaning product formulations, STPP acts as a builder that softens water by sequestering hardness ions, boosting surfactant performance in both household and industrial cleaners. Food manufacturers use it under the E451i designation as a moisture-retention and texture agent in processed meats, seafood, and dairy products to maintain quality and yield.

Water treatment operations rely on STPP to control scale formation and disperse mineral deposits in industrial cooling and boiler systems, ensuring long-term equipment protection and efficiency. In ceramics and paper production, it functions as a deflocculant, reducing slurry viscosity and improving material processability during the manufacturing and refining stages of production.

Sodium tripolyphosphate is supplied as a white powder or granule, with granulated forms preferred where dust control matters in bulk handling and large-scale industrial operations. Standard commercial grades include food-grade (FCC, E451i compliant) and technical-grade for industrial applications. Both anhydrous and hydrated forms are available for global trade.