Cas no 75-21-8 best purity 99.9%% Organic compound Ethylene Oxide Organic raw materials, hydrocarbon compounds cyclic ethers

Ethylene oxide is an organic compound with the formula C2H4O. It is a cyclic ether and the simplest epoxide: a three-membered ring consisting of one oxygen atom and two carbon atoms. Ethylene oxide is a colorless and flammable gas with a faintly sweet odor. Because it is a strained ring, ethylene oxide easily participates in a number of addition reactions that result in ring-opening. Ethylene oxide is isomeric with acetaldehyde and with vinyl alcohol. Ethylene oxide is industrially produced by oxidation of ethylene in the presence of silver catalyst.

The reactivity that is responsible for many of ethylene oxide's hazards also makes it useful. Although too dangerous for direct household use and generally unfamiliar to consumers, ethylene oxide is used for making many consumer products as well as non-consumer chemicals and intermediates. These products include detergents, thickeners, solvents, plastics, and various organic chemicals such as ethylene glycol, ethanolamines, simple and complex glycols, polyglycol ethers, and other compounds. Although it is a vital raw material with diverse applications, including the manufacture of products like polysorbate 20 and polyethylene glycol (PEG) that are often more effective and less toxic than alternative materials, ethylene oxide itself is a very hazardous substance. At room temperature it is a very flammable, carcinogenic, mutagenic, irritating, and anaesthetic gas.

Ethylene oxide is a surface disinfectant that is widely used in hospitals and the medical equipment industry to replace steam in the sterilization of heat-sensitive tools and equipment, such as disposable plastic syringes. It is so flammable and extremely explosive that it is used as a main component of thermobaric weapons;[12][13] therefore, it is commonly handled and shipped as a refrigerated liquid to control its hazardous nature.

Names
Preferred IUPAC name Oxirane[1]
Systematic IUPAC name Epoxyethane Oxacyclopropane
Other names Ethylene oxide Dimethylene oxide 1,2-Epoxyethane [3]-crown-1 Epoxide
Identifiers
CAS Number	75-21-8
3D model (JSmol)	Interactive image
Abbreviations	EO, EtO
Beilstein Reference	102378
ChEBI	CHEBI:27561
ChEMBL	ChEMBL1743219
ChemSpider	6114
ECHA InfoCard	100.000.773
EC Number	200-849-9
Gmelin Reference	676
KEGG	D03474
MeSH	Ethylene+Oxide
PubChem CID	6354
RTECS number	KX2450000
UNII	JJH7GNN18P
UN number	1040
CompTox Dashboard (EPA)	DTXSID0020600
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Properties
Chemical formula	C2H4O
Molar mass	44.052 g·mol−1[2]
Appearance	Colorless gas
Odor	Like diethyl ether[3]
Density	0.8821 g·cm−3[2]
Melting point	−112.46 °C (−170.43 °F; 160.69 K)[2]
Boiling point	10.4 °C (50.7 °F; 283.5 K)[2]
Solubility in water	Miscible
Vapor pressure	1.46 atm (20 °C)[4]
Magnetic susceptibility (χ)	−30.5·10−6 cm3/mol[5]
Refractive index (nD)	1.3597 (589 nm)[2]
Dipole moment	1.94 D[6]
Thermochemistry
Heat capacity (C)	47.9 J·mol−1·K−1[7]
Std molar entropy (S⦵298)	242.5 J·mol−1·K−1[7]
Std enthalpy of formation (ΔfH⦵298)	−52.6 kJ·mol−1[7]
Gibbs free energy (ΔfG⦵)	−13.0 kJ·mol−1[7]

Single-use medical devices, pharmaceuticals, components, and packaging that need to be sterile must be treated with an appropriate and validated technique.

It is also important to formally assess the potential effects of the sterilization process on product and packaging materials.