Sodium Sulfite Anhydrous 98% Tech Grade
Certificate Of Analysis
Product Name: Sodium Sulfite Anhydrous 98% Tech Grade
CAS: 7757-83-7
Molecular Formula: Na2SO3
| Sample date | 2024.05.10 | Quantity | 100MT |
| Batch No | ACL240510 | Production date | 2024.05.10 |
| Items | Specifications | Result | |
| Appearance | White powder or granules | White powder | |
| Na2SO3 Content % | 98.0% min | 98.2% | |
| Sodium Sulphate | 1.5% max | 1.10% | |
| Sodium Chloride (NaCl) | 0.1% max | 0.07% | |
| Iron (Fe) | 0.01% max | 0.008% | |
| Water Insoluble | 0.02% max | 0.01% | |
| Heavy Metal As PB | 10 PPM max | 4 PPM | |
| Free Alkali (as Na2SO3) | 0.30% max | 0.20% | |
| Result | Conforms to standard | ||
Sodium Sulfite Anhydrous (Na₂SO₃)
Chemical Formula: Na₂SO₃
Molar Mass: 126.04 g/mol
Appearance: White crystalline powder
Solubility: Highly soluble in water (22 g/100 mL at 20°C), insoluble in organic solvents.
Key Properties:
- Reducing Agent: Reacts with oxygen (O₂) to form sodium sulfate (Na₂SO₄):2Na2SO3+O2→2Na2SO42Na2SO3+O2→2Na2SO4
- Decomposes on Heating: Releases sulfur dioxide (SO₂) above 500°C.
- pH in Solution: Alkaline (~9–10 in water).
Uses of Sodium Sulfite Anhydrous:
- Food Industry (Preservative – E221):
- Prevents oxidation and browning in dried fruits, wines, and canned goods.
- Photography (Developing Agent):
- Used in photographic developers to prevent oxidation.
- Water Treatment:
- Removes excess chlorine (dechlorination):Na2SO3+Cl2+H2O→Na2SO4+2HClNa2SO3+Cl2+H2O→Na2SO4+2HCl
- Chemical Manufacturing:
- Intermediate in producing sodium thiosulfate (Na₂S₂O₃).
- Reducing agent in dye and pharmaceutical synthesis.
- Pulp & Paper Industry:
- Bleaching agent for wood pulp.
Safety & Handling:
- Irritant: May cause skin/eye irritation.
- Inhalation Risk: Dust can irritate respiratory tract.
- Storage: Keep in a cool, dry place, sealed to avoid moisture absorption.
- Incompatibilities: Strong oxidizers (e.g., peroxides, chlorates) → violent reactions.
Comparison with Sodium Metabisulfite (Na₂S₂O₅):
- Sodium Sulfite (Na₂SO₃): More stable, less potent reducing agent.
- Sodium Metabisulfite: Releases SO₂ more readily (stronger preservative).
