Diethylene glycol diethyl ether

Description

Diethylene glycol diethyl ether, or 2-Ethoxyethyl ether, is an organic solvent used to study the activities of enzymes in aqueous organic mixtures. Diethylene glycol diethyl ether is a solvent for reactions performed at higher temperatures. It is involved in the preparation of nitrocellulose, resins, and adhesives. It is a scrubbing medium to absorb carbonyl sulfide (COS), an impurity in petroleum refineries. It could be used as an absorbent for CO2. This absorbent has a high boiling point (462 K, in SciFinder), indicating that energy for absorbent regeneration and loss were saved. In addition, this absorbent is chemically and thermally stable, non-corrosive, and has low density and viscosity. It is rich in philic-CO2 groups, which makes Diethylene glycol diethyl ether more effective for CO2 capture. Li et al. found that carbonyl and ether groups in the absorbents improved CO2 solubility, and the carbonyl group was more effective than the ether group[1].

Chemical properties

colourless liquid

The Uses of Diethylene glycol diethyl ether

Solvent; high boiling reaction medium.

Definition

ChEBI: A polyether that consists of undecane in which the carbon atoms at positions 3, 6 and 9 are replaced by oxygen atoms.

Preparation

2-Ethoxyethyl ether could be synthesized by reacting 1, 4-dioxane with diethyl ether. ZSM-5-type zeolite was used as the catalyst. This reaction is performed in an autoclave.

General Description

Clear colorless viscous liquid.

Air & Water Reactions

Highly flammable. May be sensitive to prolonged exposure to air. Can form explosive peroxides. Vapor-air mixtures are explosive above the flash point. Water soluble.

Reactivity Profile

2-Ethoxyethyl ether is incompatible with strong acids. 2-Ethoxyethyl ether is also incompatible with strong oxidizing agents.

Fire Hazard

2-Ethoxyethyl ether is combustible.

Safety Profile

Moderately toxic by ingestion. An experimental teratogen. Other experimental reproductive effects. An eye irritant. Flammable when exposed to heat or flame. When heated to decomposition it emits acrid smoke and irritating fumes. See also GLYCOL ETHERS.

Purification Methods

Dry the ether with MgSO4, then CaH2 or LiAlH4, under N2. If sodium is used, the ether should be redistilled alone to remove any products which may be formed by the action of sodium on the ether. As a preliminary purification, the crude ether (2L) can be refluxed for 12hours with 25mL of conc HCl in 200mL of water, under reduced pressure, with slow passage of N2 to remove aldehydes and other volatile substances. After cooling, add sufficient solid KOH pellets (slowly and with shaking until no more dissolves) to give two liquid phases. The upper of these is decanted, dried with fresh KOH pellets, decanted, then refluxed over, and distilled from sodium. It can be passed through (alkaline) alumina prior to purification. [Beilstein 1 IV 2394.]

References

[1] Yun Li. “Solubilities of CO2 capture absorbents 2-ethoxyethyl ether, 2-butoxyethyl acetate and 2-(2-ethoxyethoxy)ethyl acetate.” Fluid Phase Equilibria 370 (2014): Pages 1-7.