sodium sulphite anhydrous

– product identification
cas no. : 7757-83-7
einecs no. : 231-821-4
h.s. code : 2832.100000
formula : na2so3
molecular weight : 126.04
toxicity : oral mouse ld50: 820 mg/kg
synonyms : sodium sulfite anhydrous; disodium sulfite; natrii sulphis; natrium sulfurosum;
natriumsulfit (german); sulfurous acid, disodium salt;

– physical and chemical properties
physical state : white crystalline powder
melting point : decomposes
specific gravity : 2.633
solubility in water : good
ph : 9
vapor density : 4.35
nfpa ratings : health: 1 flammability: 0 reactivity: 0
stability : stable under ordinary conditions

– applications
– pharmaceutical industry for the production of chloroform, benzene, styrene sulfone, formaldehyde.
– rubber industry as a coagulant.
– bleached cotton printing and dyeing industry as the dechlorination agent, cotton scouring agent. it can prevent the partial oxidation of cotton cloth fiber and influence the fiber strength.
– leather tanning industry for processing，make the leather soft, plump, tough, waterproof, bending, wear and other properties.
– the chemical industry for the production of vanillin hydroxyl, hydroxylamine hydrochloride and so on.
– photographic industry as a developer, etc.
– the food industry as a bleaching agent, preservatives, leavening agent, antioxidant, color agents and the insurance agent. as reducer in producing dehydration vegetables.
– electronics industry for the manufacture of photosensitive resistance.
– paper-making, electronic, water-treatment for electroplating wastewater, drinking water, etc.

– specification
testing items / quality standard – type (1) / quality standard – type (2)
appearance : white crystalline powder / white crystalline powder
purity – na2so3 : 97% min / 93% min
water insoluble : 0.02% max / 0.03% max
fe : 0.003% max / 0.005% max
free alkali, as na2co3 : 0.1% max / 0.4% max
sulphates, as na2so4 : 2.5% max / –
chlorides, as nacl : 0.1% max / –

– transportation
storage : stored in cool and dry place, avoid moisture and heat
packing : in 25kgs /50kgs /1000kgs net p.p. woven bags