|Molecular formula||C 4 H 8 S|
colorless liquid with an unpleasant odor
|External identifiers / databases|
|Molar mass||88.17 g mol −1|
1.00 g cm −3
−96 ° C
121 ° C
19 h Pa (20 ° C)
DFG / Switzerland: 50 ml m −3 or 180 mg m −3
|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|
Extraction and presentation
Tetrahydrothiophene is a colorless liquid and can already be smelled at a concentration of 0.001 ppm (reminiscent of rotten eggs, garlic, coal gas).
- Viscosity : 1.042 cp (at 20 ° C)
- Sulfur content : 36.2% (mass fraction)
- Flash point 13 ° C
- lower explosion limit (LEL): 1.1 vol% (air at 20 ° C, 1013 hPa)
- Upper explosion limit (UEL): 12.3% by volume (air at 20 ° C, 1013 hPa)
- Ignition temperature 200 ° C
THT is used as an odorant (odor = odor; odorant) in natural gas . Since natural gas is almost odorless, the regional gas suppliers vaccinate natural gas in their gas pressure regulating systems / gas pressure regulating and measuring systems with a concentration of around 20 mg · m −3 in order to give early warning of any leaky pipe installation. In addition to its unmistakable smell, THT is chemically stable. THT leaked from leaky underground lines is poorly absorbed by the ground. As a result of pipeline defects, the smell can also come to the surface. When burned with natural gas, however, it burns odorless.
As a released liquid, THT evaporates very quickly and can form highly flammable vapors when mixed with air, because the lower explosion limit is 1.1% by volume, the ignition temperature is 200 ° C, the flash point is 13 ° C. THT is comparable to gasoline in terms of fire and explosion risk. THT vapors are heavier than air and are irritating to the eyes, respiratory tract and skin. In liquid form, it is also absorbed through the skin. The LD 50 value (oral, rat) is 1750 mg kg −1 .
- Entry on tetrahydrothiophene. In: Römpp Online . Georg Thieme Verlag, accessed on September 29, 2014.
- Entry on Tetrahydrothiophene in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on February 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .
- Swiss Accident Insurance Fund (Suva): Limit values - current MAK and BAT values , accessed on November 2, 2015.
- Tetrahydrothiophene data sheet from Sigma-Aldrich , accessed on January 17, 2011 ( PDF ).
- IA Sharipova, Kh. M. Nasyrov, A. Kh. Sharipov, and MF Mazitov, "Synthesis of Tetrahydrothiophene from Tetrahydrofuran and Hydrogen Sulfide", Russian J. Org. Chem. 36 (1), 105 (2000).