Item

Index

Superior product

First-class product

Qualified product

Color of 50% aqueous solution (Pt-Co)≤

3

5

8

Crystallization point ℃                  ≥

68.9

68.8

68.5

Potassium permanganate absorption value ≤

5

8

18

Content of volatile alkali mmol/kg      ≤

0.4

0.8

1.5

290nm wave length absorbance         ≤

0.04

0.10

0.2

Aciditymmol/kg              ≤

0.05

0.10

-

Alkalinity mmol/kg              ≤

0.10

0.20

-

Iron content mg/kg              ≤

0.2

0.5

1.0

Cyclohexanone-oxime content mg/kg        ≤

20

20

-