Triethylene glycol

Structural formula
General
Surname	Triethylene glycol
other names	Triglycol; Triglycol; Triethylene glycol; 2- [2- (2-hydroxyethoxy) ethoxy] ethanol ( IUPAC ); TEG; 2,2 '- (ethylenedioxy) diethanol;
Molecular formula	C 6 H 14 O 4
Brief description	colorless, hygroscopic, almost odorless liquid
External identifiers / databases
EC number	203-953-2
ECHA InfoCard	100.003.594
PubChem	8172
DrugBank	DB02327
Wikidata	Q420630
properties
Molar mass	150.18 g mol −1
Physical state	liquid
density	1.12 g cm −3 (20 ° C)
Melting point	−7 ° C
boiling point	291 ° C
Vapor pressure	0.3 Pa (20 ° C)
solubility	miscible with water
Refractive index	1.4531 (20 ° C)
safety instructions
GHS labeling of hazardous substances	no GHS pictograms
	no GHS pictograms
H and P phrases	H: no H-phrases
	P: no P-phrases
MAK	Switzerland: 1000 mg m −3 (measured as inhalable dust )
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . Refractive index: Na-D line , 20 ° C

Triethylene glycol is a chemical compound that belongs to the group of glycols .

Manufacturing

Triethylene glycol is made by the ethoxylation of diethylene glycol . It is usually a by-product of the ethylene glycol production.

properties

Triethylene glycol is a colorless liquid that boils at 291 ° C under normal pressure . The vapor pressure function results according to Antoine according to log ₁₀ (p) = A− (B / (T + C)) (p in bar, T in K) with A = 6.7568, B = 3715.222 and C = −1 , 2995 in the temperature range from 387 to 551 K. The heat capacity at 25 ° C is 327.6 J · mol ⁻¹ · K ⁻¹ or 2.181 J · g ⁻¹ · K ⁻¹ . Triethylene glycol is a very difficult to ignite liquid. The compound only forms inflammable vapor-air mixtures at higher temperatures. It has a flash point of 177 ° C. The explosion range is between 0.9% by volume (55 g / m ³ ) as the lower explosion limit (LEL) and 9.2% by volume (580 g / m ³ ) as the upper explosion limit (UEL). The ignition temperature is 370 ° C. The substance therefore falls into temperature class T2.

use

It has only limited use as a solvent in chemistry. Due to its high boiling point, it is used for reactions that take place at high temperatures (> 200 ° C), such as the Wolff-Kishner reaction .

It is also an important intermediate in the chemical industry, for example in the manufacture of polyester resins . In addition to cyclodextrin derivatives , triethylene glycol is also used as an odor neutralizer . In addition, triglycol has the effect of drying room air and at the same time inhibiting bacteria, since the dehydrating property causes bacteria that come into contact with TEG in the air to dry out and die. In hospitals the room air is disinfected with triglycol. The dosage used in this case is considerably higher than in the commercially available aerosol sprays for the household.

TEG is also used in braking systems and hydraulic systems. TEG is also used to dehumidify and dry natural gas or to set its water dew point .

Triethylene glycol is also sometimes mentioned as an ingredient in fog fluids .

The Tobacco Ordinance allows the use of triethylene glycol as a humectant in tobacco products. In addition to propylene glycol, triethylene glycol , unlike ethylene glycol and diethylene glycol, is not classified as a hazardous substance.

Web links

Eurolite Fluids - Smoke Fluids (PDF; 205 kB)
Entry on triethylene glycol . In: P. J. Linstrom, W. G. Mallard (Eds.): NIST Chemistry WebBook, NIST Standard Reference Database Number 69 . National Institute of Standards and Technology , Gaithersburg MD

Individual evidence

↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ Entry on triethylene glycol in the GESTIS substance database of the IFA , accessed on May 21, 2012(JavaScript required) .

↑ David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Physical Constants of Organic Compounds, pp. 3-498.

↑ There is not yet a harmonized classification for this substance . A labeling of 2,2 ′ - (ethylenedioxy) diethanol in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on May 24, 2016, is reproduced from a self-classification by the distributor .

↑ Swiss Accident Insurance Fund (Suva): Limits - Current MAK and BAT values (search for 112-27-6 or triethylene glycol ), accessed on November 2, 2015.

^ Stull, DR: Vapor Pressure of Pure Substances. Organic and Inorganic Compounds in Ind. Eng. Chem. 39 (1947) 517-540, doi: 10.1021 / ie50448a022 .

↑ Stephens, MA; Tamplin, WS: Saturated liquid specific heats of ethylene glycol homologues in J. Chem. Eng. Data, 24, 81-82 (1979).

^ ^A ^b ^c E. Brandes, W. Möller: Safety-related parameters - Volume 1: Flammable liquids and gases , Wirtschaftsverlag NW - Verlag für neue Wissenschaft GmbH, Bremerhaven 2003.

↑ Safety data sheet triethylene glycol , glysofor.de, accessed on May 24, 2016.

[GESTIS-1] ↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ Entry on triethylene glycol in the GESTIS substance database of the IFA , accessed on May 21, 2012(JavaScript required) .

[CRC90_3_498-2] David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Physical Constants of Organic Compounds, pp. 3-498.

[3] Template: CL Inventory / not harmonized There is not yet a harmonized classification for this substance . A labeling of 2,2 ′ - (ethylenedioxy) diethanol in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on May 24, 2016, is reproduced from a self-classification by the distributor .

[4] Swiss Accident Insurance Fund (Suva): Limits - Current MAK and BAT values (search for 112-27-6 or triethylene glycol ), accessed on November 2, 2015.

[5] Stull, DR: Vapor Pressure of Pure Substances. Organic and Inorganic Compounds in Ind. Eng. Chem. 39 (1947) 517-540, doi: 10.1021 / ie50448a022 .

[6] Stephens, MA; Tamplin, WS: Saturated liquid specific heats of ethylene glycol homologues in J. Chem. Eng. Data, 24, 81-82 (1979).

[Brandes-7] A ^b ^c E. Brandes, W. Möller: Safety-related parameters - Volume 1: Flammable liquids and gases , Wirtschaftsverlag NW - Verlag für neue Wissenschaft GmbH, Bremerhaven 2003.