Index name

excellent grade

first grade

qualified

Appearance

colorless transparent or light yellow liquid

Phosphorus trichloride content%

≥99.5

≥99.0

≥98.5

Free phosphor content%

≤0.0001

≤0.0005

≤0.0010

Boiling range(74.5-77.5 °C)(v/v)%

≥97.5

≥97.0

≥96.0

Phosphoric acid content(PO4-2)

≤0.2

≤0.2

/

Arsenic ppm

≤1

≤3

≤5

Iron ppm

≤1

≤3

≤5

Plumbum ppm

≤1

≤3

≤5