(CAS NO.) is dried with CaSO₄, LiAlH₄, Linde type 4A molecular sieves, CaH₂, KOH, or K₂CO₃, then distd, either alone or from BaO, sodium, P₂O₅ or CaH₂. It has also been distd from zinc dust, under nitrogen. To remove traces of primary and secondary amines, triethylamine has been refluxed with acetic anhydride, benzoic anhydride, phthalic anhydride, then distd, refluxed with CaH₂ (ammonia-free) or KOH (or dried with activated alumina), and again distd.

Another purification involved refluxing for 2h with p-toluenesulfonyl chloride, then distd. Grovenstein and Williams treated triethylamine (500mL) with benzoyl chloride (30mL), filtered off the ppte, and refluxed the liquid for 1 h with a further 30 mL of benzoyl chloride. After cooling, the liquid was filtered, distd, and allowed to stand for several hours with KOH pellets. It was then refluxed with, and distd from, stirred molten potassium. Triethylamine has been converted to its hydrochloride, crystd from EtOH (to m 254 °C), then liberated with aq NaOH, dried with solid KOH and distd from sodium under nitrogen.