Editing Leblanc process (section)

== Background ==

[[Soda ash]] ([[sodium carbonate]]) and [[potash]] ([[potassium carbonate]]), collectively termed ''alkali'', are vital chemicals in the [[glass]], [[textile]], [[soap]], and [[paper]] industries.  The traditional source of alkali in western Europe had been potash obtained from [[wood]] ashes. However, by the 13th century, [[deforestation]] had rendered this means of production uneconomical, and alkali had to be imported.  Potash was imported from North America, Scandinavia, and Russia, where large forests still stood. Soda ash was imported from Spain and the Canary Islands, where it was produced from the ashes of [[glasswort]] plants (called [[barilla]] ashes in Spain), or imported from Syria.<ref>{{Cite journal|last1=Ashtor|first1=Eliyahu|last2=Cevidalli|first2=Guidobaldo|date=1983|title=Levantine Alkali Ashes and European Industries|journal=Journal of European Economic History|volume=12|pages=475–522}}</ref> The soda ash from glasswort plant ashes was mainly a mixture of sodium carbonate and potassium carbonate. In addition in Egypt, naturally occurring sodium carbonate, the mineral [[natron]], was mined from dry lakebeds. In Britain, the only local source of alkali was from [[kelp]], which washed ashore in Scotland and Ireland.<ref name="Clow52">
Clow, Archibald and Clow, Nan L. (1952). ''Chemical Revolution,'' (Ayer Co Pub, June 1952), pp. 65–90. {{ISBN|0-8369-1909-2}}.</ref><ref name="Kiefer">{{Cite journal |journal=Today's Chemist at Work |author=Kiefer, David M.|year=2002|url=http://pubs.acs.org/subscribe/journals/tcaw/11/i01/html/01chemchron.html|title=It was all about alkali|publisher=American Chemical Society |volume=11|issue=1|pages=45–6|accessdate=22 April 2007}}</ref>

In 1783, King [[Louis XVI of France]] and the [[French Academy of Sciences]] offered a prize of 2400 [[French livre|livres]] for a method to produce alkali from sea salt ([[sodium chloride]]).  In 1791, [[Nicolas Leblanc]], physician to [[Louis Philip II, Duke of Orléans]], patented a solution.  That same year he built the first Leblanc plant for the Duke at [[Saint-Denis, Seine-Saint-Denis|Saint-Denis]], and this began to produce 320 [[ton]]s of soda per year.<ref name='Aftalion11'>{{Cite book | first = Fred | last = Aftalion | title = A History of the International Chemical Industry | location = Philadelphia | publisher = University of Pennsylvania Press | year = 1991 | pages = 11–13 | isbn = 978-0-8122-1297-6}}</ref>   He was denied his prize money because of the [[French Revolution]].<ref name="Aftalion14"/>

''For more recent history, see [[#Industrial history|industrial history]] below.''