What is mono ethylene glycol (MEG)? What are its uses?

• 29 November 2023
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What is monoethylene glycol (MEG)?

Monoethylene glycol is an organic compound with the formula 2(CH2OH).

This material is mainly used for two purposes as a raw material in the manufacture of polyester fibers and antifreeze formulation.

Monoethylene glycol is an odorless and colorless liquid with a sweet taste; And in terms of appearance, it is a viscous liquid.

This compound is also known as 2 ethane, 1 diol, or MEG and antifreeze, which is the simplest organic compound.

Glycol is a type of alcohol that has two hydroxyl groups attached to carbon atoms.

The common name ethylene glycol literally means glycol derived from ethylene.

This substance is one of the most toxic compounds and eating and drinking it is very dangerous and may lead to severe illness or death.

History of Mono Ethylene Glycol (MEG):

According to most sources, French chemist Charles Adolphe Wurtz (1817-1884) first prepared monoethylene glycol in 1856.

He first combined ethylene iodide (C2H4I2) with silver acetate and then hydrolyzed the resulting ethylene diacetate with potassium hydroxide.

Wurtz called his new compound glycol; Because these compounds have quality with both ethyl alcohol (with one hydroxyl group) and glycerin (with three hydroxyl groups).

In 1859, Wurtz prepared ethylene glycol through the hydration of ethylene oxide.

There appears to have been no commercial production or use of ethylene glycol before World War I, when it was synthesized from ethylene dichloride in Germany and used as a substitute for glycerol in the explosives industry.

In the United States, semi-commercial production of ethylene glycol via ethylene chlorhydrin began in 1917.

The first large glycol production plant was built in 1925.

By 1929, almost all dynamite manufacturers used ethylene glycol.

In 1937, Carbid commissioned the first plant based on the Lefort process for the vapor phase oxidation of ethylene to ethylene oxide.

Carbide maintained a monopoly on the direct oxidation process until 1953, when the scientifically designed process was commercialized and submitted for licensing.

Tweed monoethylene glycol (MEG):

Ethylene glycol is produced from ethylene (ethene) through the intermediate ethylene oxide.

Ethylene oxide reacts according to the chemical equation to produce ethylene glycol:

C2H4O+H2O → HO−CH2CH2−OH

This reaction can be catalyzed by acids or bases, or occur at neutral pH under high temperature.

The maximum yield of ethylene glycol occurs at acidic or neutral pH with a large amount of water.

In this condition, an efficiency of 90% of ethylene glycol can be obtained.

Major by-products include oligomers of diethylene glycol, triethylene glycol and tetraethylene glycol.

Separation of these oligomers and water is energy-consuming; About 6.7 million tons are produced annually.

Using the OMEGA Shell process, higher selectivity is achieved.

In the OMEGA process, ethylene oxide is first converted to ethylene carbonate with carbon dioxide (CO).

It is then hydrolyzed with a base catalyst in a second step to produce monoethylene glycol in 98% selectivity.

Carbon dioxide is released again at this stage and can be re-entered into the process circuit.

Carbon dioxide is partially obtained from the production of ethylene oxide, where part of the ethylene is completely oxidized.

Ethylene glycol is produced from carbon monoxide in countries with large reserves and stricter environmental regulations.

Oxidative carbonylation of methanol to dimethyl

oxalate provides a promising approach for the production of C1-based ethylene glycol.

Application Usage

These applications are vital to the manufacture of a wide variety of products, including:

• Resins
• Deicing fluids
• Heat transfer fluids
• Automotive antifreeze and coolants
• Water-based adhesives
• Latex paints and asphalt emulsions
• Electrolytic capacitors
• Textile fibers
• Paper
• Leather

Production

Ethylene glycol is produced from ethylene, via the intermediate ethylene oxide
Ethylene oxide reacts with water to produce ethylene glycol according to the chemical equation

  C₂H₄O + H₂O → HOCH₂CH₂OH

This reaction can be catalyzed by either acids or bases, or can occur at neutral pH under elevated temperatures. The highest yields of ethylene glycol occur at acidic or neutral pH with a large excess of water. Under these conditions, ethylene glycol yields of 90% can be achieved. The major byproducts are the ethylene glycol oligomers diethylene glycol, triethylene glycol, and tetraethylene glycol.

Precautions: Carefully review Material Safety Data Sheets (MSDS). Overexposure through improper storage, handling or use could lead to serious health risks.

MEGlobal supports the sale of MEG for use in the traditional standard industrial applications only.

MEGlobal does not knowingly market its ethylene glycol products into non-supported applications.