Sodium triphosphate STP, also sodium tripolyphosphate (STPP), is an inorganic compound with formula Na5P3O10. It is the sodium salt of the polyphosphate penta-anion, which is the conjugate base of triphosphoric acid. Sodium tripolyphosphate is a white crystal powder with melting point at 622℃. STPP is easily soluble in water. And aqueous solution appears acid. It is provided with remarkable chelating ability to some metal ions such as Ca2+ and Mg2+, etc. But it easily aborbs moisture or water.
|Index||Industrial Grade||Food Grade|
|Assay, % ≥||94.0||94.0|
|P2O5 % ≥||57.0|| 57.0
|Water Insoluble Matter %≤||0.15||0.05|
|PH value (1% water solution)||9.2-10.0||9.5-10.0|
|Heavy Metal (as Pb) %≤||--||0.001|
|Arsenic (As) %≤||--||0.0003|
|Fluoride (F) %≤||--||0.003|
Through 16 mesh sieve %≥
Through 35 mesh sieve %≥
Trough 100 mesh sieve %≥
Applications- In food industry, Sodium tripolyphosphate is used as quality improver in the process of canned food, fruit juice drinks, foodstuffs from milk or soybeans. It may tender the meat in canned ham and soften the skin of horse bean in canned horse bean. It may also serves as a softener or densifier in foodstuff industry.
- For industry use, it is tanning agent for leather making, auxiliary for dyeing. Additionally, it is used as an oil contamination resistance agent in paper production.
It is packed with polythene bag as the inner layer, and a compound plastic woven bag as the outer layer. The net weight of each bag is 25kg.