Basic information Description Uses References Safety Related Supplier
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Sodium sulfite

Basic information Description Uses References Safety Related Supplier
Sodium sulfite Basic information
Sodium sulfite Chemical Properties
  • Melting point:500 °C
  • Density 2.63
  • refractive index 1,484
  • storage temp. Store at RT.
  • solubility H2O: 1 M at 20 °C, clear, colorless
  • form Solid
  • Specific Gravity2.633
  • color White to slightly yellow
  • OdorOdorless
  • PH9.0-10.5 (25℃, 1M in H2O)
  • PH Range9.0 - 10.5 at 126 g/l at 25 °C
  • Water Solubility 23 g/100 mL (20 ºC)
  • Sensitive Hygroscopic
  • Merck 14,8682
  • Stability:Stable. Incompatible with strong acids. Moisture and air sensitive.
  • CAS DataBase Reference7757-83-7(CAS DataBase Reference)
  • NIST Chemistry Referencesodium sulfite(7757-83-7)
  • EPA Substance Registry SystemSodium sulfite (7757-83-7)
Safety Information
Sodium sulfite Usage And Synthesis
  • DescriptionAs a soluble sodium salt of sulfurous acid, Sodium sulfite (Na2SO3) shows blenching, de-sulfurizing and dechlorinating properties which is widely applied in various fields. It is primarily used in the pulp and papermaking industry due to its blenching activity. It can serve as a good additive to help preserve the fresh appearance of good products. Besides, sodium sulfite is a component in many pharmaceuticals, which is effective to maintain the potency and stability of drugs. It can also be applied for water treatment as an oxygen scavenger agent and applied in flue gas desulfurization and preservation of photo developer solutions, etc.
  • UsesSodium sulfite (Na2SO3) is an antioxidant, used as a preservative except with meats. It is also used for water treatment and in photography and textile bleaching.
  • References
  • Chemical PropertiesSodium sulfite occurs as an odorless white powder or hexagonal prisms. Note that the commercially available sodium sulfite is often presented as a white to tan- or pink-colored powder that would not conform to the pharmacopeial specification.
  • Chemical PropertiesSodium sulfite,Na2S03, is a white,water-soluble, crystalline solid with a sulfurous, salty taste. It decomposes when heated. Sodium sulfite is used as a source of sulfite,as a chemical intermediate and food preservative, in medicine and paper manufacturing, in photographic developing, and as a bleaching agent in the textile industry. Most boiler operators use sodium sulfite for chemicals cavenging of oxygen in the feedwater. Because it decomposes into acidic gases at the high temperatures that accompany high pressures, sodium sulfite should not be used for this purpose at pressures above 122atm (12.4MPa,or 1.8 ksi).
  • Chemical PropertiesSodium sulfite is a white crystalline solid
  • Usessodium sulfite has anti-septic, preservative, and anti-oxidant properties. Sodium sulfite is also a topical anti-fungal.
  • UsesThese white crystals were prepared by passing sulfurous gas over moist sodium carbonate. Sodium sulfite is soluble in water but less so in alcohol. It was used as a preservative for alkaline developers and as a hypo clearing agent in photographic printing.
  • UsesPaper industry (semichemical pulp), reduc- ing agent (dyes), water treatment, photographic developer, food preservative and antioxidant, tex- tile bleaching (antichlor).
  • DefinitionChEBI: An inorganic sodium salt having sulfite as the counterion.
  • Production MethodsSodium bisulfite is prepared by reacting sulfur dioxide gas with sodium hydroxide solution. The solid material is obtained by evaporation of water. Further neutralization with sodium hydroxide while keeping the temperature above 33.6°C leads to crystallization of the anhydrous sodium sulfite (below this temperature the heptahydrate form is obtained).
  • Definitionsodium sulphite: A white solid,Na2SO3, existing in an anhydrousform (r.d. 2.63) and as a heptahydrate(r.d. 1.59). Sodium sulphite is solublein water and because it is readily oxidizedit is widely used as a convenientreducing agent. It is preparedby reacting sulphur dioxide with eithersodium carbonate or sodium hydroxide.Dilute mineral acids reversethis process and release sulphur dioxide.Sodium sulphite is used as ableaching agent in textiles and inpaper manufacture. Its use as an antioxidantin some canned foodstuffsgives rise to a slightly sulphuroussmell immediately on opening, butits use is prohibited in meats or foodsthat contain vitamin B1. Sodium sulphitesolutions are occasionally usedas biological preservatives.
  • General DescriptionWhite odorless powder. Density 2.633 g / cm3. Moderately toxic. Sinks in water and dissolves slowly. Also transported as a heptahydrate Na2SO3.7H2O.
  • Air & Water ReactionsSoluble in water. Reacts with hot water, steam or acids to produce corrosive material.
  • Reactivity ProfileSodium sulfite is a reducing agent, particularly under basic conditions. Reacts with oxidizing agents such as peroxides, epoxides, oxoacids. Emits toxic fumes of sodium oxide and oxides of sulfur if heated to decomposition [Lewis, 3rd ed., 1993, p. 1174].
  • HazardUse prohibited in meats and other sources of Vitamin B 1
  • Health HazardWhen ingested, solutions cause gastric irritation by the liberation of sulfurous acid. Because of rapid oxidation to sulfate, sulfites are well tolerated until large doses are reached; then violent colic and diarrhea, circulatory disturbances, central nervous depression, and death can occur.
  • Fire HazardLiterature sources indicate that Sodium sulfite is noncombustible.
  • Pharmaceutical ApplicationsSodium sulfite is used as an antioxidant in applications similar to those for sodium metabisulfite. It is also an effective antimicrobial preservative, particularly against fungi at low pH (0.1% w/v of sodium sulfite is used). Sodium sulfite is used in cosmetics, food products, and pharmaceutical applications such as parenteral formulations, inhalations, oral formulations, and topical preparations.
  • Contact allergensSodium sulfite is mainly used in photographic developers, for fixing prints, bleaching textile fibers, as a reducer in manufacturing dyes, as a remover of Cl in bleached textiles and paper, and as a preservative in the food industry for meat, egg yolks, and so on.
  • Safety ProfilePoison by intravenous and subcutaneous routes. Moderately toxic by ingestion and intraperitoneal routes. Human mutation data reported. When heated to decomposition it emits very toxic fumes of Na2O and SOx. A reducing agent. See also SULFITES.
  • SafetySodium sulfite is widely used in food and pharmaceutical applications as an antioxidant. It is generally regarded as relatively nontoxic and nonirritant when used as an excipient. However, contact dermatitis and hypersensitivity reactions have been reported. The acceptable daily intake for sodium sulfite has been set at up to 350 mg/kg body-weight daily.
    LD50 (mouse, IP): 0.950 g/kg
    LD50 (mouse, IV): 0.130 g/kg
    LD50 (mouse, oral): 0.820 g/kg
    LD50 (rabbit, IV): 0.065 g/kg
    LD50 (rabbit, oral): 1.181 g/kg
    LD50 (rat, IV): 0.115 g/kg
  • Potential ExposureSodium sulfite is used as a reducing agent; in boiler water treatment; food applications; in photographic developers and fixers; in bleaching of wool, paper, textiles, straw and silk; manufacture of dyes; dechlorination; preservation of meat, fruit and egg products; silvering of glass.
  • storageSodium sulfite should be stored in a well-closed container in a cool, dry, place. In solution, sodium sulfite is slowly oxidized to sulfate by dissolved oxygen; strong acids lead to formation of sulfurous acid/ sulfur dioxide. On heating, sodium sulfite decomposes liberating sulfur oxides.
  • ShippingUN3260 Corrosive solid, acidic, inorganic, n.o.s., Hazard class: 8; Labels: 8-Corrosive material.
  • Purification MethodsCrystallise the sulfite from warm water (0.5mL/g) by cooling to 0o. Also purify it by repeated crystallisation from deoxygenated water inside a glove-box, and finally drying it under vacuum. [Rhee & Dasgupta J Phys Chem 89 1799 1985.]
  • IncompatibilitiesA strong reducing agent. Incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases. Reacts with strong acids producing toxic sulfur dioxide.
  • IncompatibilitiesSodium sulfite is incompatible with acids, oxidizing agents, many proteins, and vitamin B1.
  • Regulatory StatusGRAS listed. Accepted for use as a food additive in Europe. Included in FDA Inactive Ingredients Database (epidural, IM, IV, and SC injections; inhalation solution; ophthalmic solutions; oral syrups and suspensions; otic solutions; topical creams and emulsions). Included in nonparenteral medicines licensed in the UK.
Sodium sulfite Preparation Products And Raw materials
Sodium sulfite(7757-83-7)Related Product Information
Sodium sulfiteSupplierMore
  • Company Name:Shanghai Aladdin Bio-Chem Technology Co.,LTD Gold
  • Tel:400-620-6333 021-20337333-801
  • Products Intro:Product Name:Sodium sulfite anhydrous
    Purity:ACS,>=98.0%(RT) Package:79RMB/500G
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  • Products Intro:Product Name:Sodium sulfite anhydrous
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  • Products Intro:Product Name:Sodium sulfite, anhydrous, 98+% (ACS)
    Purity:98+% Package:1kg;250g