Primal tar
Primary tar , also called primary tar or smoldering tar , is obtained by coking or gasification of the coal at low temperatures and differs in its extraordinarily high content of phenols , aliphatic and naphthenic hydrocarbons and the lower content of purely aromatic hydrocarbons compared to the usual higher temperatures obtained from tars . It can also be obtained from lignite and peat .
It is a low-temperature tar that is produced by hard coal distillation in a vacuum below 600 ° C or by steam distillation at temperatures below 500 ° C. This form of tar is (depending on the paraffin content) thin and red-brown. The exact composition varies with the starting material, the distillation temperature and the distillation process.
Individual evidence
- ↑ a b David Holde et al .: Hydrocarbon oils and fats . 7th edition. Springer-Verlag, 1933, ISBN 978-3-642-89045-1 , p. 559 ( limited preview in Google Book search).
- ↑ Ernst Blumer: The oil deposits . Salzwasser-Verlag, 2012, ISBN 978-3-86444-777-8 , p. 357 ( limited preview in Google Book search).
- ↑ Fritz Schreiber: Die Industrie der Steinkohlenveredelung: Summarizing presentation of the refining processes of hard coal up to the refinement of the tars extracted from it . Springer-Verlag, 1923, ISBN 978-3-663-03908-2 , p. 45 ( limited preview in Google Book search).
- ↑ Walter Fuchs : The chemistry of coal . Springer-Verlag, 1931, ISBN 978-3-642-89725-2 , p. 353 ( limited preview in Google Book search).