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What are ethylene glycols?

Mono-, di- and triethylene glycols are the first three members of a homologous series of dihydroxyalcohols. They are colourless, essentially odourless stable liquids with low viscosities and high boiling points. The three glycols have many similar chemical properties. Differences in their applications are due mainly to variations in physical properties such as viscosity, hygroscopicity and boiling point. 

Most ethylene glycol (EG) is produced by the direct hydration of ethylene oxide. Smaller amounts of diethylene glycol (DEG) and triethylene glycol (TEG) are co-produced in this process. Additional quantities of DEG and TEG can be produced by reacting EG with additional ethylene oxide.   

How are ethylene glycols used?

Glycols are widely used in industry because of their high boiling points, hygroscopicity, non-corrosiveness, freeze point depression, lubricating, plasticising and solvent properties. Additionally, their ease of chemical reaction, due to their alcohol end groups, makes them popular intermediates in the formation of numerous esters. More specifically, this is how each of the ethylene glycols are used: 

Ethylene glycol (EG): EG is by far the largest volume glycol product and is used in a variety of applications. EG is typically commercially available in three grades: fibre, industrial and antifreeze. 

The markets for EG products are polyester fibres; polyethylene terephthalate (PET) plastics; coolants in automobile antifreeze; and resins. The excellent humectant (hygroscopicity) properties of EG products also make them ideal for use in fibres treatment, paper, adhesives, printing inks, leather and cellophane. 

Diethylene glycol (DEG): DEG is an important chemical intermediate in the manufacture of unsaturated polyester resins, polyurethanes and plasticisers. Other uses for DEG depend largely on its hygroscopic properties. In natural gas processing, DEG serves as a dehydration agent. It is also used in the treatment of corks, glue, paper and cellophane. 

Triethylene glycol (TEG): the main uses for TEG depend upon its hygroscopic properties. TEG is employed as a liquid desiccant for the dehydration of natural gas. Air conditioning systems use TEG as dehumidifiers. TEG also finds use as a vinyl plasticiser, as an intermediate in the manufacture of polyester resins and polyols, and as a solvent in many miscellaneous applications. 

What are our key strengths in the ethylene glycols sector?

  • Leading position in ethylene oxide/glycol technology.    
  • World scale plants in key markets around the world.    
  • Global customer base.    
  • Proven global logistics capability. 

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