Test Item

Specification

Characteristics

White or almost white, crystalline powder or colorless crystals

Identification

Corresponds

Melting Point

189°C ~ 193°C

PH (5%,W/V)

2.1-2.6

PH (2%,W/V)

2.4-2.8

Specific Optical Rotation

+20.5° ~ +21.5°

Appearance of Solution

Clarity: Clear; Colour: ≤BY7

Heavy Metals

≤10ppm

Copper

≤5 ppm

Iron

≤2 ppm

Mercury

<1 ppm

Arsenic

≤3 ppm

Cadmium

<1 ppm

Lead

<2 ppm

Loss of Drying

≤0.4%

Sulphate Ash

≤0.1%

Oxalic Acid (Impurity E)

≤0.2%

Related substances

Impurity C:  ≤0.15%
Impurity D:  ≤0.15%
Unspecified impurities:  ≤0.10%
Total impurities:  ≤0.20%

Residual solvents

Meets the requirements

Assay

99.0%-100.5%