creosote

from Wikipedia, the free encyclopedia

Creosote , " Creosotum " or " Creosotum ", (tar oil) is a mixture of substances and is produced by the distillation of tars from fossil fuels and the pyrolysis of plant material (such as wood). The two most important industry recognized species are wood tar creosote and coal tar creosote .

Name and story

The name is derived from ancient Greek κρέας (kreas) 'meat' and ancient Greek σωτήρ (soter) 'received, preserve' and goes back to its earlier use as a preservative for meat. It was discovered in beech tar by Karl von Reichenbach in 1828 and was first used by Franz Moll in 1836 to preserve wood .

Manufacturing

  • Wood tar creosote is obtained by distilling the tar from pyrolysis. First the heavy oil fraction is treated with caustic soda . The alkaline solution is freed from the insoluble oily layer and the solution is boiled to reduce impurities. Finally, the solution is separated with dilute sulfuric acid , which leaves the crude creosote. The raw creosote is dissolved with alkalis and separated with acid and redistilled . The pure creosote is obtained from the fraction obtained at temperatures from 200 to 225 ° C.
  • Coal tar creosote is a mixture of the tar fractions that arise during coal tar distillation , but mostly from the heavy fraction.
    • Middle fraction (middle oil, carbolic oil, wash oil) from 170 ° C to 230 ° C with phenol (carbolic acid), naphthalene , cresols
    • Heavy fraction (heavy oil, creosot oil, dead oil) from 230 ° C to 270 ° C with cresols, naphthalenes, naphthols
    • Anthracene oil ( green oil ) at 270 ° C to 360 ° C with anthracene
It is re-distilled in order to adjust the phenol, naphthalene and anthracene content. The tar bases and acids are often washed out and the creosote obtained is mixed with the heavy fraction. It has been shown that the tar bases and acids do not have a major influence on the preventive effect of creosote. Tar acids are volatile and escape quickly from the wood, so there is no need for them to remain in the creosote.

composition

The various creosotes differ greatly in their composition. Manufacturers fractionate in different boiling ranges and with different mixing ratios according to customer requirements .

The following standards apply to coal tar creosote : DIN EN 13991, DIN EN 1014, DIN 68800, DIN 68811, DIN EN 12490; DIN according to WEI-IEO (West European Institute for Wood Preservation) (Grade A, B, C); BS 144; American Wood Preservers Association (AWPA) (P1-P13); ASTM D 391,246.
  • Brown coal creosote (lignite-tar creosote, "lignite oil") has a high content of tar acids , these are often extracted and added to a coal tar creosote to increase the tar acid content. From the tar acids is Kreosotnatron made or it is mixed unadulterated. It has a somewhat weaker effect than wood preservatives made from coal tar creosote.
Different origins give you different qualities. Creosote are also made from other products, these are only produced in small quantities and the effect of these creosote is significantly less.
  • Oil creosote from crude oil or oil shale ("Oil-tar creosote") is mostly mixed with coal creosote or mixed with pentachlorophenol (PCP) and also used pure.
  • Water gas creosote is produced during the distillation of the water gas . The name for it is also "Watergas-tar creosote".
  • Ultimately, the base product for peat tar creosote (“ peat tar creosote”) can be obtained from the peat tar obtained during peat distillation.

Other substances are sometimes added to the various creosotes to increase their effectiveness in specific areas or against certain pests . Various wood preservatives are used, such as PCP, arsenic , chromate copper arsenate , copper azoles or bis (N-cyclohexyldiazeniumdioxy) copper (Cu-HDO).

properties

safety instructions
CAS number
  • 8001-58-9 (creosote)
  • 61789-28-4 (creosote oil)
  • 84650-04-4 (distillates [coal tar], naphthalene oil)
  • 90640-84-9 (creosote oil, acenaphthene fraction)
  • 65996-91-0 (higher boiling distillates [coal tar])
  • 90640-80-5 (anthracene oil)
  • 8021-39-4 (beech creosote)
  • 65996-85-2 (tar acid)
  • 122384-78-5 (extract residues [coal])
GHS labeling of hazardous substances
08 - Dangerous to health

danger

H and P phrases H: 350
P: 260-280-301 + 330 + 331 + 310-303 + 361 + 353-304 + 340 + 310-305 + 351 + 338-310
Toxicological data

300 mg kg −1 ( LD 50 ,  rat ,  oral )

Beech wood creosote is described as a colorless to slightly yellowish liquid with a characteristic odor, coal creosote as a dark green-brown liquid with an aromatic tarry odor. The density is given as 1.09 g · cm −3 and the boiling point as 200–220 ° C (Beech-Tar) and 185–400 ° C (Coal-Tar).

use

The coal tar sorts with more toxic properties are mainly used as preservatives for wood protection , while the wood tar sorts are used for the storage of meat, in the "ship treatment " (wood and rope ) and for medical purposes, mainly for mouth and dental ailments as well as stomach ailments . They have an expectorant , antiseptic , astringent and anesthetic and laxative effect . The drug known as beech tar creosote is used as a cough suppressant . Creosotes have mostly been replaced by other drugs in medical use in recent years . In the veterinary Holzteerkreosot is often against hoof - and claws are suffering and for scar treatment used. Hunters also use it as a lure for red deer and wild boar , they paint it on trees and the intense smell attracts the animals that like to rub against the trees.

hazards

Some of the ingredients in creosote mixes are carcinogenic .

The placing on the market of creosote (oils) and mixtures, the use and the placing on the market of wood treated with them has been prohibited in the European Union since June 1, 2009; in Germany, similar bans have been in effect since 1991 under hazardous substances law. Under strict exceptional conditions, such as demonstrably falling below certain pollutant concentrations and compliance with occupational safety measures, creosote and wood products treated with it may be used in industry and for trade (here: including agriculture) and re-marketed. As an exception, it is also permitted to offer wood treated with it for reuse before December 31, 2002 (and thus to dispose of and use). Privileged, for example, applications for decay prevention of railroad ties and telephone poles or in agriculture for tree support or vine stakes . In general, however, certain areas of application are expressly prohibited where there is the possibility of contact with food or frequent contact with people, animals or plants. Violation of these prohibitions is a criminal offense in Germany.

Following a decision to amend the directive in July 2011, industrial use has been subject to stricter conditions since 2013. It can only be used if a special permit is granted. The member states may approve creosote if “no alternative that is at least as suitable” is available.

Web links

Commons : Creosote  - collection of images, videos and audio files

Individual evidence

  1. ↑ Emil Kopp , Richard Meyer: Chemical processing of plant and animal fibers . Ed .: Pompejus Alexander Bolley . tape 1 . Vieweg and Son, 1870, p. 229 ( full text / preview in Google book search).
  2. ↑ Ludwig Darmstaedter , René Du Bois-Reymond, Carl Schaefer: Handbook for the history of natural sciences and technology. 2nd edition, Springer-Verlag, 1908, ISBN 978-3-662-42867-2 , p. 378.
  3. ^ Friedrich Bub-Bodmar, Bernhard Tilger: The conservation of wood in theory and practice: Second part. Dogma, 2013, ISBN 978-3-95580-758-0 , p. 769.
  4. ^ Harmann Wenzl: The Chemical Technology of Wood. Academic Press, 1970, ISBN 978-0-323-14312-7 , p. 274.
  5. ^ Alfred Henry Allen: Allen's Commercial Organic Analysis. P. Blakiston's Son & Company, 1900.
  6. ^ Marshall Cavendish Corporation Staff: How It Works: Science and Technology. Marshall Cavendish, 2003, ISBN 978-0-7614-7314-5 , p. 498.
  7. ↑ George Mushrush: Petroleum Products: Instability And Incompatibility. George Mushrush, CRC Press, 1995, ISBN 978-1-56032-297-9 , p. 115.
  8. ↑ James G. Speight: The Chemistry and Technology of Coal. Third Edition, CRC Press, 2013, ISBN 978-1-4398-3646-0 , p. 517.
  9. ↑ W. P. K. Findlay: Preservation of timber in the tropics. Springer Science & Business Media, 1985, ISBN 978-90-481-8288-6 , p. 61.
  10. ↑ a b Allen W. Hatheway: Remediation of Former Manufactured Gas Plants and Other Coal-Tar sites. CRC Press, June 27, 2011, ISBN 978-0-8247-9106-3 , pp. 677 f.
  11. ^ The National Formulary: American Pharmaceutical Association, 1942, OCLC 1574867 .
  12. ↑ Kreosol on zeno.org, accessed on July 29, 2016.
  13. ^ Alfred Henry Allen: Allen's Commercial organic analysis. P. Blakiston's Son & Company, 1910, p. 353.
  14. ^ Ernest Bateman: Coal-tar and water-gas tar creosotes . Govt. Print Off., 1922, OCLC 16656516 , p. 50.
  15. ↑ James G. Speight: The Chemistry and Technology of Coal. Second Edition, M. Dekker, 1994, ISBN 978-0-8247-9200-8 , p. 456.
  16. ^ A b Concise International Chemical Assessment Document 62, Coal Tar Creosot. P. 11 (PDF; 1.08 MB), on who.int, accessed on December 2, 2016.
  17. ^ Jürgen Falbe, Manfred Regitz: RÖMPP Lexikon Chemie. Volume 2: Cm-G , 10th edition, Georg Thieme Verlag, 1997, ISBN 3-13-734710-6 , p. 394.
  18. ↑ EU standards ( Memento from March 4, 2016 in the Internet Archive ).
  19. ↑ a b c B. A. Richardson: Wood Preservation. Second Edition, Chapman & Hall, 1993, ISBN 978-1-135-82860-8 , p. 103.
  20. ↑ a b George McMonies Hunt, George Alfred Garratt: Wood preservation. McGraw-Hill, 1938, OCLC 1651958 .
  21. ↑ David Holde (Ed.): Investigation of the hydrocarbon oils and fats. 4th edition, Springer-Verlag, 1913, ISBN 978-3-662-22870-8 , p. 325.
  22. ^ Joseph Oscar Blew, Francis John Champion: Preservative treatment of fence posts and farm timbers . U.S. Dept. of Agriculture, 1967, p. 23.
  23. ^ Paul Hoering : Moor use and peat utilization with special consideration of dry distillation. Springer-Verlag, 1915, 1921, ISBN 978-3-642-98560-7 (reprint), p. 299.
  24. ^ André Wagenführ, Frieder Scholz (ed.): Pocket book of wood technology. Carl Hanser Verlag, 2012, ISBN 978-3-446-43179-9 , p. 482.
  25. ↑ Lutz Roth, Gabriele Rupp: Mixtures - Classification and labeling according to GHS. ecomed Sicherheit, 2015, ISBN 978-3-609-65196-5 , p. 121.
  26. ^ REACH for Coal Chemicals (R4CC) UVCB
  27. ^ Entry on coal tar creosote in the GESTIS substance database of the IFA , accessed on July 23, 2016(JavaScript required) .
  28. ↑ a b Datasheet Creosote from beechwood tar at Sigma-Aldrich , accessed on May 12, 2017 ( PDF ).
  29. ↑ a b data sheet creosote (PDF; 127 kB) on burmester-pharma.de, accessed on March 27, 2013.
  30. ↑ Otto-Albrecht Neumüller (Ed.): Römpps Chemie-Lexikon. Volume 3: H-L. 8th revised and expanded edition. Franckh'sche Verlagshandlung, Stuttgart 1983, ISBN 3-440-04513-7 , p. 2235.
  31. ↑ Kreosotum on cysticus.de, accessed on July 20, 2016.
  32. ↑ Article 67 of Regulation (EC) No. 1907/2006 of the European Parliament (so-called REACH-VO) with its Annex XVII, entry 31 for the substances listed there in column 1
  33. ↑ by the tar oil ordinance , then the chemical ban and the hazardous substances ordinance in conjunction with the ChemG
  34. ↑ Art. 67 REACH Regulation Annex. XVII no. 31 col. 2 para. 3
  35. ↑ § 5 no. 21 ChemSanktionsV , § 27 ChemG.
  36. ↑ Europa on site, July 27, 2011: Stricter requirements for the carcinogenic wood preservative creosote ( Memento of August 27, 2016 in the Internet Archive ).