Triethylene glycol, also known as triglycol, with the English name Triethylene glycol. It is a colorless, transparent, slightly sweet-smelling, stable viscous liquid. Freezing point -7.2°C, melting point -4.3°C, boiling point 289.4°C, 134°C (0.267kPa), relative density (15°C) 1.1274, refractive index 1.4578 (15°C), ignition point 173.9°C, flash point 330°C (closed cup), combustion point 412.8°C, vapor pressure 1Pa (20°C). It is miscible with water, ethanol, benzene, and toluene, poorly soluble in ethers, and insoluble in petroleum ether. It is hygroscopic. It contains oxygen atoms and hydroxyl groups connected to alkyl groups, thus exhibiting the properties of both alcohols and ethers.

Production process of triethylene glycol: It is produced as a by-product (accounting for about 0.5%-1%) during the hydration of ethylene oxide to produce ethylene glycol.

Applications of triethylene glycol: Used as an excellent dehydrating agent for natural gas, oilfield associated gas, and carbon dioxide; used as a solvent for nitrocellulose, rubber, resins, oils, paints, pesticides, etc.; air disinfectant; plasticizer for polyvinyl chloride, polyvinyl acetate resins, glass fibers, and asbestos pressed boards in the form of triethylene glycol esters; tobacco anti-drying agent, fiber lubricant, and natural gas desiccant; also used in organic synthesis, such as in the production of high-boiling-point brake fluids with good low-temperature performance.