|
Items
|
Index
|
|||
|
Tech Grade
|
Food Grade
|
|||
|
Na2S2O4, % ≥
|
85
|
88
|
90
|
85
|
|
Fe, ppm ≤
|
20
|
20
|
20
|
---
|
|
Zn, ppm ≤
|
1
|
1
|
1
|
1
|
|
As, ppm ≤
|
---
|
---
|
---
|
1
|
|
Heavy Metal(as Pb), ppm ≤
|
---
|
---
|
---
|
1
|
|
Water Insolubles, % ≤
|
0.4
|
0.4
|
0.05
|
0.05
|
