Triethylamine

TEA

Colorless to yellowish oily liquid with ammoniacal ( in dilution fishy ) odor

Liquid

0.73 g · cm -3

-115.0 ° C

89 ° C

70 hPa ( 20 ° C)

10.76 (25 ° C)

Good in water ( 133 g · l-1 at 20 ° C)

1.4010

Risk

1 mg · m -3; 4.2 ppm

Template: Infobox chemical / molecular formula search available

Triethylamine (TEA) is a basic solvent and a tertiary amine of formula N ( CH2CH3 ) 3, its molecular formula is sometimes abbreviated as Et3N.

Properties

In comparison to the simple amine, ammonia, all of three hydrogen atoms are replaced by ethyl groups. This makes the molecule less volatile and much more lipophilic ( non-polar ). It is similar to ammonia salt like compounds with acids, called triethylammonium salts.

At 1013 hPa (normal pressure ) of triethylamine with water called a lower critical solution temperature even lower critical solution temperature of 18.5 ° C. That is, below this temperature, triethylamine is miscible with water, and above this temperature has a miscibility gap.

Production

Technically, triethylamine obtained in the gas phase by alkylation of ammonia with ethanol.

Use

In the organic synthetic chemistry, triethylamine is used as basic solvent. Furthermore, it is often used as an auxiliary base to in reactions liberated acids to bind ( this, see also: diisopropylethylamine ). As an example the formation of esters from carboxylic acid chlorides and alcohols may be mentioned, is released in the hydrochloric acid. The binding of the acid takes place through the formation of triethylammonium salts, in the case of hydrochloric acid so triethylammonium chloride (see also: Hydrochloride). Furthermore, it is in the production of various plastics and resins such as polyurethanes and phenolic resins, as the catalyst used.

It also can be used as a component of rocket fuels (patent of BMW aircraft engines from 1943, inter alia, see Tonka ) are used. It is also used as a raw material for the production of pesticides, pharmaceuticals, paints and coating materials. As fuel " tracer " in experimental Transparent engines, it can be used for laser-induced fluorescence ( LIF). To excite a UV laser is used in this case.

In the foundry art, triethylamine is used to achieve a chemical reaction and therefore a hardening of the sand - binder mixture ( cold-box process). Here, gaseous triethylamine for 30 to 60 seconds, is introduced into the sand - binder mixture. This is followed by curing of the mold at room temperature. Triethylamine can also be used to increase the pH value in triethylene glycol (TEG). TEG is used in the dehydration.

Hazards and preventive measures

The substance causes severe burns of the respiratory tract by inhalation of vapors, some with bloody sputum, as well as the skin, eyes and other mucous membranes in the local contact. When First aid for inhalation poisoning can be administered in high doses Auxiloson ® spray. In case of skin contact helps prompt rinsing with plenty of water and then blotting with polyethylene glycol ( PEG) 400 Take off contaminated clothing. The further treatment is left to the doctor immediately hinzuzuziehenden. If the eyes are affected, as the first affected eye ( eye wash, etc. ) at least ten minutes, rinse with plenty of water and consult an eye specialist. If swallowed, vomiting should be avoided and the person should drink plenty of fluid. Again, a doctor must be consulted / involved. Systemic consequences of intoxication, nausea, vomiting and headache are known. Triethylamine is highly flammable. The use of open flames in the workplace is prohibited. Prophylactic are when working with triethylamine protective clothing, gloves and possibly to wear respiratory protection.

In case of danger with absorbent material ( Rapid Rench, Chemizorbï, sand, sawdust) and dispose of as hazardous waste. Apply For small fires, CO2 extinguishers, water or foam.

During long-term exposure to triethylamine shows mutagenic properties. About classification as a carcinogen is not yet decided.