Sodium Hydrogen Sulphite Extra Pure

1. Basic Identification Attributes

• Chemical Name: Sodium Hydrogen Sulphite
  • CAS Number: 7631-90-5
  • HS Code: 2831.20.00
  • Molecular Formula: NaHSO₃
  • Synonyms:

• Sodium bisulfite
• Sodium bisulphite
• Disodium hydrogen sulfite

2. Physical & Chemical Properties

Physical State: Solid (crystalline powder)
• Color & Odor: White to pale yellow, pungent sulfur dioxide odor
• Melting Point: Decomposes before melting (approx. 150 °C)
• Density: About 1.48 g/cm³
• Solubility:

• Highly soluble in water
• Insoluble in ethanol
  • pH Level: Acidic to neutral aqueous solution (pH ~4-5)
  • Vapor Pressure: Not significant
  • Flash Point: Not flammable

3. Safety & Hazard Attributes

Hazard Class (GHS Classification):

• Skin irritation (Category 2)
• Eye irritation (Category 2A)
• Respiratory sensitizer in some cases
  • NFPA Ratings:
• Health: 2
• Flammability: 0
• Reactivity: 1
  • Exposure Limits:
• No specific OSHA PEL; avoid inhalation of dust and fumes
  • Reactivity:
• Decomposes releasing sulfur dioxide gas on heating
• Reacts with acids releasing toxic gases

4. Storage & Handling Attributes

Storage Conditions:

• Store in a cool, dry, well-ventilated area away from acids and oxidizers
• Keep containers tightly closed
  • Incompatible Materials:
• Strong acids
• Oxidizing agents
  • Container Type:
• Plastic or sealed metal drums
  • Shelf Life:
• Stable if kept dry and sealed
  • Special Handling Requirements:
• Use protective gloves, goggles, and dust mask
• Avoid dust generation and inhalation

5. Regulatory & Compliance Attributes

Regulatory Status:

• Approved for limited food use as preservative (E221)
• Listed under REACH and EPA inventories
  • Transportation Restrictions:
• Not classified as hazardous for transport under normal conditions
  • Waste Disposal Method:
• Dispose according to local environmental regulations; avoid release to environment

6. Environmental & Health Impact

Ecotoxicity:

• Moderate toxicity to aquatic life; avoid discharge into waterways
  • Persistence in Environment:
• Breaks down relatively quickly under aerobic conditions
  • Carcinogenicity/Mutagenicity:
• Not classified as carcinogenic or mutagenic
  • Biodegradability:
• Biodegradable with moderate persistence