·Specification: industry grade HG/T 2074-1991 JIS K 1476-1995
food grade GB 2682-1995

Item	90%	88%	85%	food grade
Na2S2 O4	≥ 90%	≥ 88%	≥ 85%	≥ 85%
(Fe)	≤ 20ppm	≤ 20ppm	≤ 20ppm	≤ 20ppm
(Zn)	≤ 1ppm	≤ 1ppm	≤ 1ppm	≤ 1ppm
Clarity	Clarify	Clarify	Clarify	Clarify
EDTA	-	-	-	Qualified
(As)	-	-	-	≤ 1ppm
Other heavy metals(pb)	-	-	-	≤ 1ppm
HCHO	-	-	-	≤ 0.05%
water insoluble matter	≤ 0.05%	≤ 0.05%	≤ 0.05%	-

Uses:
1, It is for vat dyes staining the reducing agent, reducing hair bleaching agents, vat dyes printing auxiliaries, silk scouring and bleaching agent, dyeing agents and objects of the peel color dye vat cleaning agent in the textile industry.
2, It is used as a mechanical pulp, mechanical pulp mill hot and deinking pulp bleaching agent in pulp and paper industry.
3, It is used as sugar, candy, candied fruit, caramel, cookies, fans, etc. bleach and food preservation agent in the food industry.
4, As a bleaching agent is widely used to restore the kaolin bleaching; fur whitening bleaching and restore; bamboo products and straw products such as bleach.
5, It is used as a reducing agent in chemical industry.
6, Packing: Barrels sealed packaging, polyethylene film bag lined with double-layer 15KG/20KG/25KG/50KG/100KG/200KG