Product name

Phosphoric acid

Molecular formula

H3PO3

CAS Number

13598-36-2

Molecular weight

82

United Nations code

2834

Physicochemical properties

Phosphorous acid is a colorless crystal. The relative density is 1.651 (21.1℃), the melting point is 73.6℃, and the boiling point is 200℃ (decomposition). It is easily soluble in water and alcohol, slowly oxidized to orthophosphoric acid in air, and decomposed into orthophosphoric acid and phosphine (very toxic) when heated to 180 °C. Phosphorous acid is a dibasic acid. The acidity of phosphorous acid is slightly stronger than that of phosphoric acid. It has strong reducibility and is easy to reduce Ag ions into metallic silver, which can reduce sulfuric acid to sulfur dioxide. Phosphorous acid also has strong hygroscopicity and deliquescence.

Product Usage

It is mainly used to produce phosphite, synthetic fiber and organophosphorus pesticides, and is also used to produce high-efficiency water treatment agent ATMP.

Main indicators

Test items

Superior product

First grade

Main content (in terms of H3PO3), %≥

99

99

Iron (in terms of Fe), %≤

0.001

0.003

Chloride (in terms of CL), %≤

0.01

0.02

Sulfate (SO4), %≤

0.008

0.01

Phosphate (based on PO4sub>), %≤

0.2

0.6

Exterior

Pure white crystal

White crystals

70% aqueous solution test 70%

Colorless and transparent

Colorless, transparent and free of impurities

Packaging, storage and transportation

The woven bag is lined with plastic bags or kraft paper lined with plastic bags. Net weight 25kg, 500kg or 1000kg.