Sodium Hydroxide (NaOH): Essential Alkali for Industrial and Chemical Applications

Technical Introduction

Sodium Hydroxide (NaOH), commonly known as caustic soda or lye, is a strong inorganic base widely used in chemical, industrial, and household applications. It is highly alkaline, hygroscopic, and strongly reactive with acids and many organic materials.

• Chemical Formula: NaOH

• CAS Number: 1310-73-2

• Molecular Weight: 39.997 g/mol

• Appearance: White solid (pellets, flakes, granules) or colorless liquid (aqueous solution)

• Properties:

  • Highly soluble in water (exothermic dissolution)

  • Strongly alkaline, reacts with CO₂ in air to form sodium carbonate

  • Corrosive to organic tissues and metals in moist conditions

Applications

1. Chemical Industry

• Raw material for soaps, detergents, and surfactants

• Used in textile processing, paper pulping, and bleaching

• Essential in the manufacture of organic and inorganic chemicals (sodium salts, dyes, pharmaceuticals, etc.)

2. Water Treatment

• pH adjustment in municipal and industrial water treatment

• Neutralization of acidic wastewater

3. Food Industry (Food-Grade NaOH)

• Peeling fruits and vegetables

• Cocoa and chocolate processing

• Olives curing

• Production of caramel color and soft drinks (pH control)

4. Pharmaceuticals & Healthcare

• Production of aspirin, anticoagulants, and other medicines

• Used as a cleaning and sanitizing agent in medical facilities

5. Household & Cleaning Products

• Drain cleaners and oven cleaners (dissolves grease and organic matter)

• Soap and detergent manufacturing

6. Petroleum & Energy Industry

• Refining petroleum products

• Used in biodiesel production (transesterification catalyst)

✅ Advantages

• Strong alkalinity makes it highly effective in neutralization and saponification.

• Versatile — used across food, chemical, water, and energy industries.

• Cost-effective large-scale industrial chemical.

• Readily available worldwide in solid or liquid forms.

• High solubility in water ensures rapid action in aqueous systems.

⚙️ Technical Specifications (Typical Parameters)

⚠️ Safety & Regulatory Notes

• Corrosive: Causes severe burns to skin, eyes, and mucous membranes.

• Handling Precautions:

  • Use protective gloves, goggles, face shield, and clothing.

  • Store in sealed containers away from acids and moisture.

• Environmental Impact: Highly alkaline effluents can harm aquatic life if not neutralized.

• Regulatory Approval:

  • Approved for controlled use in food processing (E524).

  • Strict safety handling required under OSHA, EU REACH, GHS.

❓ FAQ

Q1: What is the difference between caustic soda flakes, pearls, and liquid?
They are all NaOH with the same chemistry; the difference is only the physical form (solid flakes, beads/pearls, or aqueous solution).

Q2: Is sodium hydroxide safe in food?
Yes, food-grade NaOH (high purity) is used under controlled conditions for peeling, curing, or pH adjustment. It is not consumed directly but removed or neutralized.

Q3: Why is NaOH used in soap making?
It reacts with fatty acids in oils/fats in a process called saponification, producing soap and glycerin.

Q4: Can sodium hydroxide dissolve organic matter?
Yes. It breaks down proteins, fats, and greases, which is why it is used in drain cleaners.

Q5: What precautions should be taken when handling NaOH?
Always wear protective equipment, avoid inhalation of dust/fumes, and ensure proper ventilation. If contact occurs, wash immediately with water.