Acetic Anhydride | CAS 108-24-7
Basic Information
| Property | Value |
|---|---|
| CAS Number | 108-24-7 |
| Chemical Name | Acetic anhydride / Ethanoic anhydride |
| Molecular Formula | C4H6O3 |
| Molecular Weight | 102.09 g/mol |
| Appearance | Colorless clear liquid |
| Purity (GC) | ≥ 99.0% |
| Density (20°C) | 1.082 g/mL |
| Boiling Point | 139–140 °C |
| Flash Point | 49 °C (closed cup) |
| UN Number | UN1715 — Class 8, Subsidiary 3 |
Introduction
Acetic anhydride (CAS 108-24-7) is one of the most important acylating agents in industrial chemistry — the acid anhydride of acetic acid. It is highly reactive toward water, alcohols, and amines, making it a versatile reagent for acetylation reactions across the pharmaceutical, textile, and food industries.
China is the world's largest producer, accounting for over 60% of global capacity. Key Chinese manufacturers operate large integrated facilities ensuring consistent quality and competitive FOB pricing.
⚠️ Regulatory note: Acetic anhydride is a Table 2 controlled precursor under the UN Convention Against Illicit Traffic in Narcotic Drugs. International trade requires end-use certificates and import permits. Sunchem assists customers with all compliance documentation.
Key Applications
Pharmaceutical Industry
- Aspirin synthesis (acetylsalicylic acid) — one of the world's highest-volume pharmaceutical compounds
- Paracetamol/acetaminophen intermediate
- Steroid acetylation
- Penicillin and cephalosporin intermediate chemistry
Cellulose Acetate & Textile
- Cigarette filter tow (largest single industrial application globally)
- Cellulose acetate fibers (apparel, linings)
- Cellulose acetate film (photographic, packaging)
- Cellulose acetate plastic (frames, tool handles)
Chemical Synthesis
- Vinyl acetate monomer production (intermediate)
- Perfume and flavor industry (acetylation of terpene alcohols)
- Herbicide and pesticide synthesis
- Starch modification
Food & Feed
- DATEM (diacetyl tartaric acid esters of monoglycerides) — bread improver
- Acetylated distarch phosphate — modified food starch
Safety & Handling
- Flammable liquid (flash point 49°C); reacts vigorously with water releasing acetic acid
- Use in well-ventilated areas; vapors are corrosive to eyes and mucous membranes
- UN1715; Hazard Class 8 (Corrosive), Subsidiary: 3 (Flammable)
- Dual-use chemical — import permits required in most countries
Packaging
- 200 L iron drums (~216 kg net)
- IBC containers (1,000 L)
- ISO tank containers for large-volume orders
FAQ
Q: Is acetic anhydride regulated for export from China?
Yes — Table 2 controlled precursor. Export requires end-use certificates and import permits from destination country. Sunchem assists with all required compliance documentation.
Q: What purity grades are available?
Industrial grade (≥99.0% GC) and pharmaceutical grade (≥99.5%, with heavy metals and residual solvent testing). Specify required grade when quoting.
Q: What is the typical lead time from China?
2–4 weeks from order confirmation. Air freight available for small urgent orders; sea freight recommended for >1 MT.
Q: How should acetic anhydride be stored?
Tightly sealed corrosion-resistant containers (stainless steel or HDPE). Away from water, strong oxidizers, and ignition sources. Temperature: 5–25°C. Shelf life: 12 months.