Triethylene Glycol (TEG) is a larger molecule than MEG, DEG and has two ether groups. It is less clear and less hygroscopic than DEG, but has a higher boiling point, density and viscosity.
The properties of TEG resemble those of DEG, but it is heavier. TEG is also distinguished by its antibacterial properties.
TEG is an important non-volatile industrial solvent. It is also useful in the dehydration of gases, manufacture of insecticides and in the synthesis of some organic derivatives. Pure TEG is useful in the production of plasticizers for cellophane, glue, cork, powdered ceramics and some plastics. TEG is a component in the formulation of some pigments, printing dyes, inks and pastes. It is also used for air fumigation.
STORAGE AND HANDLING
TEG may be stored in ordinary carbon steel containers. However, for ease of handling and to maintain its purity, special precautions should be taken. To avoid contamination by iron, TEG storage tanks should be made of stainless steel (type 304 or 316) or aluminum. If contamination by halides is undesirable, the packing of the valves and the gaskets should be made of asbestos or halide-free materials.
TEG is loaded after thorough cleaning and drying of tanks, and nitrogen purging to ensure that it remains chloride, iron, and ash-free. It can be shipped in big vessels, tankers of various sizes and in lined steel drums. Precautionary labeling, “Triethylene Glycol. For Industrial Use Only.”