GLACIAL ACETIC ACID
Paint chemicals 2025-03-21
Acetic acid (Acetic Acid) is a colorless and transparent liquid with a stimulating sour smell. When the purity of acetic acid reaches 99.5wt% or more, it is called Glacial Acetic Acid. Acetic acid is soluble in water, alcohols and ethers, and is widely used in man-made fibers, rubber, plastics, agriculture, herbicides, leather, organic salts, dyestuffs, textiles and other industries.
Glacial Acetic Acid: Overview and Key Properties
| Category | Details |
|---|---|
| Chemical Name | Glacial Acetic Acid |
| IUPAC Name | Ethanoic Acid |
| Molecular Formula | CH₃COOH |
| CAS Number | 64-19-7 |
| Appearance | Colorless liquid |
| Odor | Pungent vinegar-like smell |
Physical & Chemical Properties
| Property | Value |
|---|---|
| Purity | ≥99.5% (glacial grade) |
| Melting Point | 16.6°C (61.9°F) |
| Boiling Point | 118.1°C (244.6°F) |
| Density (20°C) | 1.049 g/cm³ |
| Viscosity (25°C) | 1.22 mPa·s |
| Flash Point | 39°C (102°F) |
| pKa Value | 4.76 (25°C) |
Production Methods
| Method | Process Description |
|---|---|
| Methanol Carbonylation | Rhodium/iodide catalyzed (Monsanto process) |
| Oxidation of Acetaldehyde | Metal catalyst (traditional method) |
| Biological Fermentation | Vinegar production (dilute acetic acid) |
Applications
| Industry | Uses |
|---|---|
| Chemical Manufacturing | Vinyl acetate monomer (VAM) production |
| Pharmaceuticals | Solvent, pH adjuster, intermediate |
| Food Industry | Acidulant (E260), preservative |
| Textiles | Dyeing processes, cellulose acetate |
| Laboratory Use | Chemical reagent, buffer solution |
Safety & Handling
| Parameter | Requirements |
|---|---|
| OSHA PEL | 10 ppm (TWA) |
| NFPA Rating | Health 3. Flammability 2. Reactivity 1 |
| Storage | Glass/plastic/stainless steel containers |
| First Aid | Flush with water (15 min for skin/eye contact) |
Comparison with Other Acids
| Acid | Glacial Acetic vs. Alternatives |
|---|---|
| Formic Acid | Less corrosive, higher pKa |
| Hydrochloric Acid | Weaker acid, less volatile |
| Citric Acid | Organic but solid at room temp |
Market Data
| Aspect | Details |
|---|---|
| Global Capacity | ~18 million tons/year |
| Price Range | 600−600−900/ton |
| Major Producers | Celanese, BP, Eastman, Jiangsu Sopo |
Environmental Impact
| Characteristic | Data |
|---|---|
| Biodegradability | Readily biodegradable |
| Aquatic Toxicity | LC50 (fish): 50-100 mg/L |
| Atmospheric Lifetime | ~2 weeks |
Key Advantages and Limitations
| Advantages | Limitations |
|---|---|
| Versatile chemical intermediate | Corrosive to metals |
| High purity available | Freezes at 16.6°C |
| Biodegradable | Strong irritating vapors |
Summary
Glacial acetic acid is a fundamental organic acid with wide industrial applications, particularly in VAM production and food processing. Its unique freezing property (forming ice-like crystals at 16.6°C) gives the “glacial” designation. While safer than mineral acids, proper handling is essential due to its corrosivity and irritating vapors. The methanol carbonylation process dominates modern production.
