Editing Tetraethyllead (section)

=== Antiknock agent ===
A gasoline-fueled reciprocating engine requires fuel of sufficient [[octane rating]] to prevent uncontrolled combustion (pre-ignition and [[engine knock|detonation]]).<ref name="Seyferth" /> Antiknock agents allow the use of higher [[compression ratio]]s for greater [[fuel efficiency|efficiency]]<ref name="SAEtrans-hce1959">{{cite tech report |last1=Caris |first1=D. F. |last2=Nelson |first2=E. E. |year=1959 |title=A New Look at High Compression Engines |number=590015 |doi=10.4271/590015 |publisher=Society of Automotive Engineers }}</ref> and peak [[power (physics)|power]].<ref>{{cite journal|last1=Loeb|first1=A. P.|title=Birth of the Kettering Doctrine: Fordism, Sloanism and Tetraethyl Lead|journal=Business and Economic History|date=Fall 1995|volume=24|issue=2|url=http://www.thebhc.org/sites/default/files/beh/BEHprint/v024n1/p0072-p0087.pdf|archive-url=https://web.archive.org/web/20151027191244/http://www.thebhc.org/sites/default/files/beh/BEHprint/v024n1/p0072-p0087.pdf|archive-date=2015-10-27|url-status = live}}</ref> Adding varying amounts of additives to gasoline allowed easy, inexpensive control of octane ratings. TEL offered the business advantage of being commercially profitable because its use for this purpose could be patented.<ref name=Kovarik2005 /> Aviation fuels with TEL used in WWII reached octane ratings of 150 to enable turbocharged and supercharged engines such as the [[Rolls-Royce Merlin]] and [[Rolls-Royce Griffon|Griffon]] to reach high horsepower ratings at altitude.<ref>{{cite book|title = I Kept No Diary|author = F. R. Banks|date = 1978|publisher = Airlife Publishing, Ltd.|isbn = 978-0-9504543-9-9}}</ref> In military aviation, TEL manipulation allowed a range of different fuels to be tailored for particular flight conditions.{{citation needed|date=September 2021}}

In 1935 a license to produce TEL was given to [[IG Farben]], enabling the newly formed German {{lang|de|[[Luftwaffe]]}} to use high-octane gasoline for high altitude flight. A company, Ethyl GmbH, was formed that produced TEL at two sites in Germany with a government contract from 10 June 1936.<ref>[[Rainer Karlsch]], Raymond G. Stokes. ''"Faktor Öl". Die Mineralölwirtschaft in Deutschland 1859–1974.'' C. H. Beck, München, 2003, {{ISBN|3-406-50276-8}}, p. 187.</ref>

In 1938 the United Kingdom [[Air Ministry]] contracted with [[Imperial Chemical Industries|ICI]] for the construction and operation of a TEL plant. A site was chosen at Holford Moss, near Plumley in Cheshire. Construction started in April 1939 and TEL was being produced by September 1940.<ref name="Plumley TEL Works">{{cite web |title=Northwich |url=https://www.octelamlwch.co.uk/northwich/ |website=Octel Bromine Works |access-date=9 January 2022 |archive-date=11 January 2022 |archive-url=https://web.archive.org/web/20220111091720/https://www.octelamlwch.co.uk/northwich/ |url-status=live }}</ref>