... STPP with high quality and competitive price STPP Sodium Tripolypyosphate(industrial grade)ItemStandard NoExact NoSodium Tripolypyosphate(Na5P3O10),% ... % ≤0.100.07PH value9.2-10.09.4Whiteness, ≥85.090Fe,% ≤0.0150.009 Sodium Tripolypyosphate(food grade)Item NoInspection ItemStandard ... 1Qualified3Insoluble substance in water, %≤0.050.03Qualified4 PH value 9.5-10.09.6Qualified5Arenic(base on As),%≤0.00030. ...