... .8-7.35.8-6.55SolubilityQualifiedQualified6Heavy metals, as Pb %≤ --0.0017Arsenic, as As%≤ --0.00038Fluoride as F%≤ --0.0039Water insoluble %≤0.050. ... > Sodium Hexametaphosphate's Application:a) For industrial use, such as oil field, paper-making, textile, dyeing, petrochemical industry, ... and building material industry;b) it is mainly used as additive agent, PH adjusting agent and fermentation agent, ...