1.Both food & tech grade
2.Steady high quality
3.Nicest price &Good service
4.Prompt delivery

1. Appearance: White Free Flowing Fine Crystal or Powder2. Specifications:Specification For Food Grade and Industry Grade:

Item	Quality Index
	Food Grade	Industry Grade
Purity ( As Na2S2O5)	98.0% min	96.0% min
Sulfur Dioxide( SO2)	65.0% min	65.0% min
Arsenic ( As )	0.0002% max	-
Heavy metals ( As Pb )	0.0005% max	-
Selenium (Se )	0.0005% max	-
Iron (Fe)	0.001% max	0.002% max
Water insoluble	0.02% max	0.05% max
PH value :	4.0-4.8	4.0-4.8
Remark :	Conformed with FCC V and E 223 Standard

 Specification for Pharmaceutical Grade and Photo Grade 

Item	Quality Index
	Pharmaceutical Grade	Photo Grade
Purity ( As Na2S2O5)	98.0% min	98.0% min
Sulfur Dioxide( SO2)	65.0% min	65.0% min
Thiosulphate ( As S2O3) :	0.05 % max	0.05% max
Chloride ( As CL-) :	30 ppm max	50ppm max
Arsenic ( As ) :	1ppm max	1ppm max
Lead ( Pb ) :	1 ppm max	2ppm max
Copper (Cu) :	1 ppm max	1ppm max
Iron (Fe ) :	5 ppm max	5ppm max
Mercury (Hg) :	0.1ppm max	1ppm max
Chromium (Cr) :	1 ppm max	-
Selenium (Se ) :	1 ppm max	5ppm max
Zinc (Zn)	1 ppm max	1ppm max
Cadmium (Cd )	1ppm max	-
Nickel (Ni)	1ppm max	-
Na2SO3 + Na2SO4	1.5% max	-
PH value :	4.0-4.8	4.0-4.8
Remark :	Conformed with USP standard

 3. Application :( 1) Food Grade: Bleach agent (e.g. candies, cake, bamboo shoots, etc); Loose agent (e.g. bread, cracker etc); Antiseptic and germicide (e.g. fruit juice, tinned food, brews, the cereals food is defended storage etc); Inhibitor and freshen agent (e.g. day lily, seafood, fruit and vegetable etc).(2) Industry Grade: Mordant of printing and dyeing; Dechlorinate of textile after bleaching; Sulphonated agent and reducer of chemical industry and pharmacy; Bleach of paper pulp, bamboo and timber bleach of Stap; Treatment agent of waste water; Rubber solidifying agent Perfume industry is served as hydro carbon perfume aldehyde
The hide profession employ to do to molt dose and pliable dose and wearproof dose; sewage treatment, and so on .(3) Pharmaceutical Grade: In chemical synthesis in the production of acrylic fibre, vitamin K, vitamin A, pharmaceutical intermediates, etc.(4) Photo Grade: The sensitize industry is served as the developing agent reductant and the protection of fixing bath dose.4. Package: Packed in 25kg plastic woven bag, 25kg Kraft paper bag, 25kg PE bag, 500kg jumbo bag or as per the buyer's requirement.