Synonyms: Disodium disulfite; Disodium metabisulfite; Disodium pyrosulfite; Natrium metabisulfurosum; Natriummetabisulfit; Sodium disulfite; Sodium pyrosulfite;
Sodium metabisulphite application use in mining:
- Depression of Zn sulphide (sphalerite) and Fe sulphide (eg. pyrite, pyrrhotite) minerals.
Cyanide detoxification in gold mining- Sodium metabisulphite precipitate gold from gold dissolved in aqua regia (auric acid). It is also used as a source of sulphur dioxide, mixed with air or oxygen for the destruction of cyanide in commercial gold cyanidation process. This makes it a suitable alternative to ferrous sulphate heptahydrate.
Other uses: Flux for decomposing minerals; substitute for sulphuric acid in dyeing; disinfectant; manufacture of sodium hydrosulphide, sodium sulphate and soda alum; liberating carbon dioxide in carbonic acid baths, in thermophores; carbonising wool; manufacture of magnesia cements, paper, soap, perfumes, foods, industrial cleaners, metal pickling compounds; laboratory reagent.
Most gold plants around the world are required by law to destroy cyanide and metal cyanide complexes in their tailings prior to discharge from the metallurgical site into the natural environment. Process leach residues are detoxified with sodium bisulphite and air (by batch), prior to discharge to leach residue ponds.
WHAT INFLUENCES PROCESS SELECTION?
There are a number of technologies available for destroying cyanide and its metal complexes, and the choice of the best method for a particular application is not simple. Complexity arises because:
• environmental regulations vary with respect to allowable concentration limits in the treated tailings,
• the various detoxification techniques vary widely in their ability to eliminate certain species,
• the chemical composition of the tailings from each plant is unique,
• reagent consumption and cost varies from one country and location to the next.
COST EFFECTIVENESS IS CRITICAL
The cost of treating cyanide tailings can be a significant percentage of total operating costs, and unlike other operating costs, yields no economic “return”. It is therefore very important, for both regulatory and economic reasons, to select the correct process, and then optimize the operating conditions to minimize reagent dosages. This requires a good knowledge of local regulations as well as skillful laboratory test work and piloting.
Other uses of Sodium metabisulphite : It is used in waste water treatment, in the pulp and paper industry, in the photographic industry and in various other industries as a bleach or dechlorinator. It can also be used to treat flue gases to remove sulfur trioxide (SO3). Sodium bisulfite solution is sometimes used as a food additive. Sodium bisulfite solution can also be used in the manufacture of other chemicals.
Appearance White monoclinic crystalline
Form, crystalline or granular solid/
Odor: slight sulfurous odor
Boiling point: N/A
Melting/freezing point: :180 °C
Specific gravity: 2.43
Flash point: Non-flammable
pH: 1.3 (1% aqueous solution)
1. TRANSPORT INFORMATION
- Transport-UN 2693
- Hazard Class No. :5.1 Oxidizing Agent
- Packing Group: II
- HS Code: 28321000
2. STORAGE & HANDLING & HANDLING
Store in a cool, dry, well ventilated place and out of direct sunlight. Store away from foodstuffs. Store away from incompatible materials . Keep containers closed when not in use - check regularly for spills..
3. Download our Sodium Metabisulphite (SMBS) msds for more safety and handling information.