Epoxyethane most fondly called ethylene oxide (abbreviated as EO or ETO) with a molecular formula of C2H4O or (CH2CH2)O is an organic compound and a cyclic ether that has a sweet smell and is highly flammable.
Regarded as the simplest epoxide, epoxyethane reacts with other compounds to form ring openings. It is also used in various industries like the medical industry, the plastic industry, and lots more.
It is odorless, colourless, and has a highly flammable nature makes it a major constituent in the production of explosives. Furthermore, It is anesthetic, irritating, and carcinogenic at room temperature, and is oftentimes transported as a liquid in a bid to term its lethal nature.
However, its reactivity has also fostered its use in the pharmaceutical industry for the sterilization of medical equipment.
According to reports, over 20 billion medical devices are sterilized each year by epoxyethane.
Preparation Of Epoxyethane
Epoxyethane can be produced by the treatment of 2-chloroethanol with potassium hydroxide.
Cl-CH2CH2-OH + KOH = (CH2CH2)O + KCl + H2O
Industrially, it is produced by oxidizing ethylene in the presence of a silver catalyst.
H2C= CH2 + O = C2H4O
Ethylene Oxide can be prepared by decomposing ethylene carbonate in the presence of hexachloroethane at a temperature of 392 – 401°F ( 200 – 210°C).
Epoxyethane can be prepared by the treatment of calcium oxide with ethyl hypochlorite.
2 CH3CH2 – OCl + CaO = 2 (CH2CH2)O + CaCl2 + H2O
It can also be produced by reacting diiodo ethane with silver oxide.
I-CH2CH2-I + Ag2O = (CH2CH2)O
Chemical Properties Of Epoxyethane
Epoxyethane reacts with ethanol to form polyethylene glycol ethers.
(CH2CH2)O + C2H5OH = HO-CH2CH2-OC2H5
Epoxyethane reacts with triethylamine in the presence of water to form choline.
(CH2CH2)O + (CH3)3N + H2O = [HOCH2CH2N(CH3)3]+OH-
It reacts with carboxylic acid like acetic acid and its anhydride in the presence of catalysts to form glycol di and monoesters.
(CH2CH2)O + CH3CO2H = HOCH2CH2-O2CCH3
(CH2CH2)O + (CH3CO)2O = CH3CO2CH2CH2O2CCH3
Ethylene oxide reacts with dialkylamino ethanols to form amino polyethylene glycols.
n (CH2CH2)O+ R2NCH2CH2OH = R2NCH2CH2O – (-CH2CH2O-)n-H
Ethylene oxide passes through an aqueous solution of metal halides to form halohydrins.
2 (CH2CH2)O + C2Cl2 + 2 H2O = 2 HO – CH2CH2 – Cl + Cu(OH)2
The addition of water in epoxyethane leads to the production of ethylene glycol.
(CH2CH2)O + H2O = HOCH2CH2OH
Epoxyethane reacts with hydrogen cyanide to form ethylene cyanohydrin.
(CH2CH2)O + HCN = HO-CH2CH2-CN
Physical Properties Of Epoxyethane
Epoxyethane is a flammable, odorless, and colourless gas which has an ether-like sweet odor. It is miscible in water and has a vapor pressure of 20°C.
It has a molar mass of 44.052 g-mol-1, and a density of -0.88 gcm-3. It melts at -112.46°C and -170.43°F and boils at 10.4°C and 50.7°F.
Uses Of Epoxyethane
• It is used in the production of thickeners.
• It is used as a major component in the production of polyethylene glycol(PEG).
• It is used to process storage facilities.
• It is used in the large-scale production of industrial chemicals.
• It is used as a sterilization agent in the medical industry.
• It is used to accelerate the maturity process of tobacco leaves.
• It is used as a raw material in the production of polysorbate 20.
• It is used as a major constituent in the production of fuel-air explosives.
• It is used as a pesticide.
• It is used in the clothing industry for packaging.
• It is used as a fungicide.
• It is used in the production of ethanolamines, polyglycol ethers, mono-ethylene, diethylene, tri ethylene, and polyethylene glycols which are in turn used in the production of antifreeze, thinners, lubricants, polyester, and lots more.
Despite its enormous uses and benefits in different industries, ethylene oxide is a very lethal substance.
Epoxyethane has a very high carcinogenic, mutagenic and neurotoxic potential and affects respiration hence long-term exposure to it can lead to leukemia, reproductive effects, breast cancer, dizziness, cataracts, pancreatic cancer, neurotoxicity, lymphoma, coma, stomach cancer, seizure.
Short-term exposure to ethylene oxide can lead to cyanosis, weakness, lung injury, skin burns, difficulty in breathing, diarrhea, vomiting, headache, frostbite, reproductive effects, eye burns, and nausea.
Exposure to epoxyethane can be by:
• Working in pharmaceutical companies which use it to sterilize its supplies and equipment, by working in industries that produce it, by working in agricultural firms which use it to regulate insects, by working in industries that produce adhesives, detergents, solvents etc.
• Living near these industries, heating cooking oils etc.
• Consuming products like tobacco which contains it or pharmaceutical products which are sterilized by it.
However, to avert this, the Occupational Safety and Health Administration (OSHA) has set limits to the level of exposure for workers in this industries and has also ordered for the provision of adequate safety clothing for each worker.
In addition, countries have placed laws on the emission of epoxyethane from industries producing and using it.