Sodium Metabisulfite
Property: white or light yellow crystal powder, a strong smell of sulfur dioxide,relative density is 1.4, easy to dissolve in water and glycerin, water solution. It has acidity,and its solubility will become large while raising the temperature and is less to dissolve in ethanol.
Molecular Formula : Na2S2O5
Molecular Formula : Na2S2O5
Molecule Weight : 190.12
CAS NO .: 7681-57-4
Appearance : White Free Flowing Fine Crystal or Powder
Packing: Packed in 25kg plastic woven bag, 25kg Kraft paper bag, 25kg PE bag, 500kg/1000kg/1100kg/1200kg jumbo bag or as per the buyer's requirement.
Specification For Food Grade and Industry Grade :
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Item
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Quality Index
|
|
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Food Grade
|
Industry Grade
|
|
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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 :
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Conformed with FCC V and E 223 Standard
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|
Specification for Pharmaceutical Grade and Photo Grade
|
Item
|
Quality Index
|
|
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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) :
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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 :
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Conformed with USP standard
|
|
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 .
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.
Storage: Store the product in a dry and cool place.
Next product： Sodium carbonate(soda ash)