Stpp (sodium tripolyphosphate) Properties: White powder; melting point 622ípc; easily soluble in water; it has got salient chelating capacity to ions of ca and mg etc. And can soften hard water to make suspension solution become into clear solution; it has got weak alkalinity but no corrosiveness. It is a surfactant, and has got outstanding emulsification to lubricants and fat. It has different bulk density, i.E. Low density 0.35-0.5g/cm3, medium density 0.51-0.65g/cm3 and high density 0.66-0.9g/cm3. This product has two crystalline forms, namely type i (high temperature type) and type ii (low temperature type). The chemical properties of the two types are the same, and the difference between them lies in the thermostability, hygroscopicity, and solubility and hydration heat when dissolving. Food grade Guaranteed technical specifications: No.Specifications 1assayna5p3o10 % min 95.0 2p2o5 % min 57.0 3water insoluble matter % max0.05 4iron(fe) %max 0.01 5ph value(1%water solution) 9.5-10.0 6heavy metal (as pb) % max 0.001 7arsenic (as) %max 0.0003 8fluoride (f) % max 0.003 9whiteness %min 90.0 Stpp (sodium tripolyphosphate) In 25kg, 50kg, 1000kg net bags, store at a cool, dry and well ventilated place.