Diethyl ether

What is diethyl ether?

Diethyl ether (C₄H₁₀O), also known as ethoxyethane, is a colourless, highly volatile liquid with a characteristic sweet odour. It was historically used as an anaesthetic but is now primarily employed in laboratory settings for solvent extraction, particularly in the isolation of organic compounds from aqueous solutions. Its low polarity and ability to dissolve a wide range of organic substances make it valuable in organic synthesis and purification processes.

Why is diethyl ether hazardous?

Diethyl ether poses significant safety risks due to its high flammability and the formation of explosive peroxides upon prolonged exposure to air and light. These peroxides can accumulate in stored samples and detonate during distillation or evaporation. Therefore, it must be stored in dark, airtight containers with stabilisers such as butylated hydroxytoluene (BHT) and tested regularly for peroxide formation. Additionally, its low boiling point (34.6 °C) necessitates use under controlled conditions to prevent inhalation hazards and fire risks.

How is diethyl ether regulated?

Due to its flammability and potential for peroxide formation, diethyl ether is subject to strict handling and storage regulations under frameworks such as GHS, REACH, and ISO standards. Laboratories must follow safety protocols including the use of explosion-proof equipment, proper ventilation, and the use of SDS and CoA documents to ensure compliance. It is also listed under TSCA and may require special handling permits in certain jurisdictions.

Related concepts

Diethyl ether is often compared to other ethers such as tetrahydrofuran (THF) and diisopropyl ether (DIPE), which share similar solvent properties but differ in reactivity and safety profiles. Its use is increasingly limited in favour of safer alternatives in industrial and academic settings.