STPP/sodium tripolyphosphate Parameter GradeStandard: GB/T9984-2008/QB1034-1991 Technical FoodAssay Na5P3O10 % ≥ 94.095.0P2 O 5 % ≥ 57.057.0Water Insoluble Matter % ≤ 0.150.05Iron(Fe) % ≤ 0.0150.015PH value (1% water solution) 9.2-10.09.4-10.0Heavy Metal (as Pb) % ≤ -0.001Arsenic (As) % ≤ -0.0003Fluoride (F) % ≤ -0.003Chloride(Cl) % ≤ -0.025Sulphate(SO4)% ≤ -0.4Whiteness % ≥ 90.090.0Density (g/cm3) 0.35-0.950.55-0.90Phase I 10-3010-30