Mono Ethylene Glycol (MEG)

Ethylene glycols are primarily used for two purposes: as a raw material in producing polyester fibers and as an antifreeze formulation. Monoethylene glycol (MEG), also known as ethylene glycol, is an essential solvent with the chemical formula C2H6O2, a molecular weight of 62 grams, and a melting point of 12.9ºC. It is a polar compound that is a colorless, odorless liquid with a sweet taste and is soluble in water. Monoethylene glycol is one of the most important commercial glycols used in the production of polyester fibers, fabrics, bottles, and as a coolant. It is also a major component of antifreeze.

Why is this substance preferred over other antifreeze agents? One advantage of using this compound in antifreeze agents is its better heat transfer properties compared to other chemical compounds used, such as propylene glycol. Additionally, compared to propylene glycol, it has lower viscosity at zero temperature. The high viscosity of other substances can lead to higher energy consumption and increased costs. Economically, this substance is also more cost-effective because a lower percentage of MEG is required compared to propylene glycol to achieve the same necessary freezing point when mixed with water.
55% of monoethylene glycol usage is dedicated to the production of polyester fibers, and 25% of MEG is used in packaging and polyethylene terephthalate (PET) bottles. MEG is one of the key winners for thermoplastic resins in the plastics industry. It is widely used as a precursor for polyester fibers and resins.
Oil and Gas In this industry, MEG is used as a thermodynamic hydrate inhibitor. MEG is added to natural gas to prevent the formation and freezing of hydrates in pipeline systems and to protect against system corrosion.
The global production capacity of this substance was approximately 40 million tons in 2018, with about 40% of that attributed to Asian countries. This significant role of Asia is related to its large number of textile and fabric producers, which require polyester and polyethylene terephthalate. China, India, and Taiwan are among the largest producers of this substance in the Asia-Pacific region.
The demand and purchase for this product are strongly influenced by its applications. In 2018, the global demand for this substance was approximately 33 million tons, with textile factories, bottle manufacturers, antifreeze producers, and chemical production plants accounting for the highest demand with 50%, 23%, 7%, and 4.5% respectively.

Monoethylene glycol is produced from ethylene using an intermediate called ethylene oxide. In this process, ethylene and water react to produce ethylene glycols, including MEG, DEG, and TEG (trimethylene glycol). It is interesting to note that this reaction can be carried out in different pH environments, but it is recommended to perform the reaction in an acidic or neutral environment with additional water for higher yields.

Production stages: In the first stage, ethylene and oxides are introduced into a multi-tube reactor to produce ethylene oxide. This exothermic reaction occurs in fixed beds inside the reactor tubes, usually in the gas phase (the catalyst used is silver on an alumina base). Water vapor is produced during the reaction.

Monoethylene glycol (MEG) is a versatile chemical compound used in a wide range of applications. Some common uses of MEG include:

Antifreeze

MEG is commonly used as an antifreeze agent in the automotive industry to prevent the formation of ice in cooling systems.

Polyester Resins

It’s a key ingredient in the production of polyester resins, which are widely used in the manufacture of various products, including boats, automotive parts, and construction materials.

Textile Industry

is used in the textile industry to improve the moisture absorption of fabrics, making them more comfortable to wear.

Solvent

is used as a solvent in various applications, including inks, dyes, and paints.

Personal Care Products

MEG is used in various personal care products, such as lotions and shampoos, as a moisturizing agent.

Deicing Fluids

is also used as a component in deicing fluids for airplanes, helping to prevent the formation of ice on the wings and other critical surfaces.

This substance is used in the production of the following materials:

• Heat transfer fluids
• Water-based adhesives
• Latex paints and asphalt emulsions
• Electrolytic capacitors
• Leather
• Antifreeze and deicing additives
• Intermediate in chemical reactions and polymer production
• Solvent for plastics, lacquers, and dyes
• Additive to fuels, heat exchange fluids, brakes, and hydraulic systems
• Water repellent
• Printing ink coupling agents
• Textile softeners
• Solvent for dyes in textile and leather dyeing
• Raw material in agricultural formulations
• General cleaners
• Explosive materials
• Electrolyte components
• Moisture retainers
• Water coatings
• Preservatives, rust inhibitors, and disinfectants

Monoethylene glycol is classified as a toxic and hazardous substance for human health and ingestion.

Due to its high toxicity, the use of this substance is prohibited in the following cases:

• Water supply equipment
• Food, drug, and cosmetic manufacturing and formulation
• Anti-freeze in water tanks
• Anti-freeze in fire suppression systems