Phosphorous acid or Phosphoric acid CAS 7664-38-2 is a kind of colorless viscous liquid which is widely used in food industry as a great food additive and in the industries. Phosphorous acid is an important raw material of fertilizer production including almost all kinds of Phosphorous fertilizers. Also, for the pharmaceutical industry, Phosphorous acid is alse applied to produce its some materials.

Specification:
Food Grade:
Purity (H3PO4)               85% min
As 0.00005%                 max
F                                  0.001% max

Heavy Meta(as Pb)         0.0005% max
H3PO3                          0.012% max

Technical Grade
Purity (H3PO4)               85% min
Cl                                  0.0005% max
SO4                              0.005% max
Fe                                 0.002% max
As                                 0.005% max
Heavy Meta(as Pb)         0.001% max
Color                             30 max

LCD Grade
Purity (H3PO4)               85% min
Fe                                 300 ppb max
As                                 200 ppb max
Na                                 150 ppb max
Ca                                 150 ppb max
Mg                                150 ppb max
Pb                                 100 ppb max
Cu                                 100 ppb max
K                                   100 ppb max
Ni                                  100 ppb max
Al                                  100 ppb max
Mn                                 100 ppb max
Bi                                  100 ppb max
Co                                 100 ppb max
Sr                                  100 ppb max
Color                              10 max.

Application

For food industry, as a acidity regulator and nutrition agent for yeast, Phosphoric acid of food grade could be applied for flavors, canned food and light drinks as well as used in wine brewery as a nutrients source for yeast to prevent the reproduction of useless bacteria. 

For technical grade industry, phosphoric acid could be used to produce variety of phosphates, electrolyte treatment liquids or chemical treatment liquids, refractory mortar with phosphoric acid and inorganic coheretant. It is also used as a catalyst, drying agent and cleaner. In coating industry it is used as a rust-proof coating for metals.