Borax (Sodium Tetraborate)
Natural mineral-derived versatile compound — Used in cleaning, agriculture, industry, and many more areas
Overview
Borax (Sodium Tetraborate Decahydrate, CAS No: 1303-96-4) is a naturally occurring boron mineral. It is a white crystalline substance, soluble in water, and used in a wide variety of industrial, agricultural, and household applications.
Borax has been known and used since ancient times. Today it is widely used in cleaning products, insecticides, fire retardants, metallurgy, and many other fields. Borax is the sodium salt of boric acid and is obtained by refining natural boron minerals.
Applications
Borax has a wide range of industrial, agricultural, and household uses:
Cleaning Products
Used as a natural cleaner and disinfectant. Effective as a water softener, stain remover, and laundry booster in detergents. Main ingredient in homemade cleaning solutions.
Insecticide
Effective pesticide against cockroaches, ants, and other insects. Damages insects' exoskeletons. Used in homes and agriculture.
Metallurgy
Used as a flux in welding and soldering. Cleans oxide layers from metal surfaces and improves weld quality. Especially common with non-ferrous metals.
Fire Retardant
Used as a fire retardant in wood, textiles, and other flammable materials. Added to construction materials due to its flame-retardant properties.
Agriculture
Source of trace element (boron) for plants. Used as soil conditioner and fungicide. Improves plant growth in boron-deficient soils.
Cosmetics & Personal Care
Used as pH adjuster and preservative in some cosmetic products. Acts as emulsion stabilizer in lotions and creams.
Technical Specifications
| Property | Value | Unit | Test Method |
|---|---|---|---|
| Chemical Name | Sodium Tetraborate Decahydrate | - | - |
| Other Names | Borax, Sodium Borate | - | - |
| CAS Number | 1303-96-4 | - | - |
| EC No | 215-540-4 | - | - |
| Formula | Na₂B₄O₇·10H₂O | - | - |
| Molecular Weight | 381.37 | g/mol | - |
| Appearance | White crystalline powder or granules | - | Visual |
| Odor | Odorless | - | - |
| Purity | ≥99.5 | % | ASTM E11 |
| Boron Oxide (B₂O₃) Content | ≥36.5 | % | ASTM E11 |
| Water Content | 47.2 ± 0.5 | % | Karl Fischer |
| pH Value (1% sol.) | 9.2-9.4 | - | ISO 1842 |
| Solubility (Water, 20°C) | 5.3 | g/100 mL | ISO 918 |
| Density | 1.73 | g/cm³ | ISO 787 |
| Melting Point | 75 (dissolves in water), 743 (anhydrous) | °C | ISO 6321 |
| Lead (Pb) Content | ≤5 | mg/kg | ISO 172 |
| Arsenic (As) Content | ≤3 | mg/kg | ISO 2590 |
Safety Information
Hazard Symbols and Statements
Toxic Irritant Environmental Hazard
Personal Protective Equipment (PPE)
- Dust mask (in high dust concentrations)
- Chemical-resistant gloves (nitrile or neoprene)
- Goggles or face shield (against dust or solution splash)
- Lab coat or protective clothing
Storage Conditions
- Store in a cool, dry, and well-ventilated place
- Keep in original packaging, tightly closed
- Storage temperature: 15-30°C
- Keep away from acids and strong oxidants
- Protect from moisture, prevent water contact
Fire Fighting
- Non-combustible substance
- May release toxic gases when decomposed at high temperatures
- Suitable methods: Water spray, dry chemical powder, CO₂
- Firefighting personnel must use full respiratory protection
Handling and Storage
Transportation
- Ensure containers are tightly closed
- Prevent moisture contact
- Transport separately from acids and food items
- Have absorbent material available for spills
- Provide ventilation during transport
Storage
- Store in dry, cool, and well-ventilated areas
- Display appropriate signage in storage area
- Protect from direct sunlight
- Store on elevated shelves
- Storage temperature should not exceed 40°C
Spill Response Measures
- Evacuate exposed personnel from area
- Use appropriate personal protective equipment
- Collect spill by dry method (sweeping)
- Do not use water — may form solution
- Wash spilled area with plenty of water
Regulatory Information
GHS Classification
- Acute Toxicity (Oral) Category 4
- Eye Irritation Category 2
- Reproductive Toxicity Category 1B
- Acute Aquatic Hazard Category 1
Important Regulations
- REACH: Registered
- EPA: Listed in TSCA inventory
- European Biocidal Products Regulation: Annex I
- FDA: Limited use in food contact
- Restricted in children's toys
Compliance Certificates
- ISO 9001:2015 Quality Management System
- ISO 14001:2015 Environmental Management System
- OHSAS 18001 Occupational Health & Safety
- Food contact compliance (for specific batches)
Environmental Information
Environmental Impact
Borax can be toxic to aquatic organisms at high concentrations. It may accumulate in soil and be taken up by plants. Environmental impact depends on usage amount and application method. When used correctly, the environmental risk is low, but direct mixing into water sources should be prevented.
Biodegradation
- Soil: Slowly degrades into borate ions
- Water: Converts to soluble borate forms
- Air: Non-volatile, does not degrade
Waste Management
- Classified as hazardous waste
- Dispose in accordance with local regulations
- Do not discharge to sewers or surface waters
- Work with licensed disposal companies for large quantities
- Neutralization method can be applied for waste disposal
Frequently Asked Questions
How is borax used in household cleaning?
Borax can be added to laundry detergent (½ cup), used as a stain remover (made into paste), toilet cleaner (¼ cup borax + 1 cup vinegar), and carpet cleaner. However, it should not be used on food-contact surfaces.
Is borax safe?
Borax is considered safe when used appropriately, but ingestion, inhalation, or prolonged skin contact should be avoided. Keep away from children and pets. Not for food contact. May cause skin irritation in sensitive individuals.
Are borax and boric acid the same thing?
No, borax (sodium tetraborate) and boric acid are different compounds. Borax is the sodium salt of boric acid. Borax is more alkaline (pH 9.2) while boric acid is mildly acidic (pH 5.1). Both contain boron but have different chemical properties and applications.
What should I do if borax contacts my skin?
Remove contaminated clothing immediately and wash skin thoroughly with soap and water. Seek medical attention if irritation persists. In case of eye contact, rinse eyes with plenty of water for at least 15 minutes and seek immediate medical help. If swallowed, rinse mouth with water, do not induce vomiting, and seek medical attention immediately.
How is borax used in agriculture?
Borax serves as a boron source for plants. Typically, a solution of 1 teaspoon borax per liter of water is prepared and sprayed on leaves or applied to soil. Used for plants showing boron deficiency symptoms (stunted growth, leaf deformation). Excessive use can harm plants.