What is Mono Ethylene Glycol – Fibre?
Mono ethylene glycol (also known as MEG, EG, 1,2-ethanediol or 1,2-Dihydroxyethane) is an organic compound with the formula C2H6O2. It is a slightly viscous liquid with a clear, colourless appearance and a sweet taste that emits virtually no odour. It’s miscible with water, alcohols, and many other organic compounds and is primarily used in the industry for manufacturing polyester fibres and as a component in the production of antifreeze, coolants, aircraft anti-icers and de-icers.
Chemical and physical properties of mono ethylene glycol:
Molecular Formula: C2H6O2 / (CH2OH)2 / HOCH2CH2OH
Synonyms: monoethyleneglycol, mono ethyl glycol, meg glycol, ethylene glycol, 1,2-ethanediol, Ethane-1,2-diol, EG, industrial glycol, 1,2-Dihydroxyethane, glycol alcohol.
Cas Number: 107-21-1
Molecular Mass: 62.07 g/mol
Exact Mass: 62.036779 g/mol
Flashpoint: 232 °F/ 111.11 °C
Boiling Point: 387.7 °F / 197.6 °C at 760 mm Hg
Melting Point: 9 ° F / -12.8 °C
Vapour Pressure: 0.06 mm Hg at 68 °F / 20 °C
Water Solubility: Miscible
Density: 1.115 at 68 °F
How is it produced?
Mono ethylene glycol is produced industrially using ethylene oxide via hydrolysis. Ethylene oxide is obtained through oxidation and is then reacted with water to give mono ethylene glycol with di and tri ethylene glycols as co-products:
C2H4O + H2O → HOCH2CH2OH
Mono ethylene glycol is also manufactured via the hydrogenation of dimethyl oxalate in the presence of a copper catalyst or via the acetoxylation of ethylene.
Handling, storage and distribution
Hazards and toxicity
Mono ethylene glycol has an NFPA health rating of 2, indicating that overexposure to the skin and eyes can cause irritation and residual injury. Inhaling vapours is not deemed hazardous; however consumption of liquid form can cause injury. It has a flammability rating of 1 which indicates that it requires sufficient preheating for ignition to occur. An instability rating of 0 suggests that mono ethylene glycol is usually stable. Mono ethylene glycol’s vapours are heavier than air and will travel to surrounding areas.
Safety and responses
If contact is made with the eyes, immediately wash with plenty of water and seek medical attention. If the skin is contaminated, remove all wet clothing and wash the skin with water. In the case of excessive inhalation, breathe fresh air and seek medical attention. Alcohol-resistant foam or water spray should be used to fight fires and spillages should be prohibited from reaching water sources and sewers. Appropriate PPE equipment should be worn when handling mono ethylene glycol to protect the skin and eyes.
Storage and distribution
Mono Ethylene Glycol can be stored in stainless steel, aluminium, or lined drums, tank cars, or tank trucks. It has a specific gravity of 1.115 and a flash point of 110 °C (closed cup). It is not regulated for transport on road, rail, air, or sea but it is classified as harmful, and is harmful if swallowed.
What is mono ethylene glycol used for
A primary industry use of mono ethylene glycol is in antifreeze applications where it is a component in the manufacture of antifreeze, coolants, aircraft ani-icer and de-icers due to its ability to depress the freezing temperature of water. It is also used in hydraulic brake fluids and cooling systems such as in vehicles and air-conditioning units as it acts as a coolant and heat transfer agent.
There is strong global demand for Mono ethylene glycol in the plastic industry as it is a vital ingredient in the production of polyester fibres, films, and resins, one of which is polyethylene terephthalate (PET). PET is then converted into plastic bottles which are used globally. It is estimated that 70-80% of all the MEG consumed is used as a chemical intermediate in these polyester production processes.
Mono ethylene glycol is also used as a solvent in paints and electrolytic condensers, as a desiccant in gas pipelines to prohibit the formation of clathrates, as a chemical intermediate in the production of capacitors, as an industrial humectant in fibres, adhesives, cellophane, synthetic waxes. It is also found in other industrial products such as plasticizers, processing aids, adhesives, additives and surface treating agents.
Mono ethylene glycol is found in many consumer products such as antifreeze, ani-icer, de-icers, brake fluids, adhesives, automotive care products, cosmetics, toners, fabrics, inks, pens, paints, plastics and coatings.