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
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 :

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                  0.05 % max                0.05% max
S2O3) :

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
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.
Storage:Store the product in a dry and cool place.

Application:

7681-57-4