... Hexametaphosphate Industrial Grade (1) Total phosphate, as P2O5: 68.0% min. (2) Inactive phosphate, as P2O5: 7.5% max. (3) PH ... . (6) Iron, as Fe: 0.05% max. Usage: Used in industries of oil fields, paper production, textile, dyeing, petroleum, chemistry, metallurgy and ... Hexametaphosphate Food Grade (1) Total phosphate, as P2O5: 68.0% min. (2) Inactive phosphate, as P2O5: 7.5% max. (3) PH ...