Sodium Metasilicate
Other Names
-
Sodium Silicate (when specific ratios, but commonly refers to metasilicate)
-
Sodium Trisilicate
-
Na₂SiO₃
CAS Number: 6834-92-0
Chemical Formula: Na₂SiO₃
Molecular Weight: 122.06 g/mol
📘 1. Definition
Sodium Metasilicate is a white, granular or crystalline solid that is highly alkaline and soluble in water. It is widely used as a builder in detergents, cleaning agents, and water treatment, and also serves as a corrosion inhibitor, pH regulator, and chemical intermediate. Sodium metasilicate is valued for its strong alkalinity, good solubility, and low cost, making it common in both industrial and household products.
🧪 2. Physical & Chemical Properties
| Property | Value |
|---|---|
| Chemical Formula | Na₂SiO₃ |
| Molecular Weight | 122.06 g/mol |
| Appearance | White granular or crystalline solid |
| Odor | Odorless |
| Melting Point | 1088 °C |
| Density | 2.4 g/cm³ |
| Solubility | Soluble in water, insoluble in alcohol |
| pH | Strongly alkaline (pH ~12–13 for 10% solution) |
| Stability | Stable under normal conditions; hygroscopic |
🧰 3. Applications / Uses
| Industry | Applications |
|---|---|
| Detergent & Cleaning | Builder in laundry detergents, dishwasher powders, industrial cleaners |
| Water Treatment | pH adjustment, sequestrant, corrosion inhibitor |
| Ceramics & Glass | Binder, deflocculant, glaze component |
| Textiles | Scouring agent, dyeing aid |
| Pulp & Paper | Pulp processing, paper coating |
| Chemical Industry | Intermediate for silicate compounds, adhesives, cement additives |
| Metal Treatment | Rust removal, metal surface preparation |
⚠️ 4. Safety & Handling
| Hazard | Details |
|---|---|
| Health | Corrosive; causes skin and eye irritation; inhalation of dust may irritate respiratory tract |
| Environmental | Generally low environmental toxicity; avoid release into waterways |
| PPE | Gloves, goggles, protective clothing, dust mask recommended |
| Storage | Store in a cool, dry place, away from acids and moisture |
| Handling | Avoid inhalation of dust; use proper ventilation; wash skin after contact |
📌 5. Summary
Sodium Metasilicate is a highly alkaline, water-soluble solid used primarily as a detergent builder, pH regulator, corrosion inhibitor, and chemical intermediate. Its strong alkalinity, solubility, and versatility make it essential in detergents, water treatment, ceramics, textiles, and chemical industries. Proper handling and protective measures are necessary due to its corrosive nature.
