Editing Phenol (section)

===Older methods===
Early methods relied on extraction of phenol from coal derivatives or the hydrolysis of benzene derivatives.

====Hydrolysis of benzenesulfonic acid====
The original commercial route was developed by [[Bayer]] and [[Monsanto]] in the early 1900s, based on discoveries by [[Charles Adolphe Wurtz|Wurtz]] and [[August Kekulé|Kekulé]].  The method involves the reaction of a strong base with [[benzenesulfonate|benzenesulfonic acid]], proceeded by the reaction of hydroxide with [[sodium benzenesulfonate]] to give sodium phenoxide. Acidification of the latter gives phenol. The net conversion is:<ref name="Wittcoff">Wittcoff, H.A., Reuben, B.G. Industrial Organic Chemicals in Perspective. Part One: Raw Materials and Manufacture. Wiley-Interscience, New York. 1980.</ref>
:{{chem2|C6H5SO3H + 2 NaOH -> C6H5OH + Na2SO3 + H2O}}

====Hydrolysis of chlorobenzene====
[[Chlorobenzene]] can be hydrolyzed to phenol using a base ([[Dow process (phenol)|Dow process]]) or steam ([[Raschig–Hooker process]]):<ref name="chemistry.org">{{cite web |url=http://www.chemistry.org/portal/a/c/s/1/feature_pro.html?id=c373e908e6e847ac8f6a17245d830100 |title=Direct Routes to Phenol |access-date=2007-04-09 |url-status=dead |archive-url=https://web.archive.org/web/20070409042033/http://www.chemistry.org/portal/a/c/s/1/feature_pro.html?id=c373e908e6e847ac8f6a17245d830100 |archive-date=2007-04-09 }}</ref><ref name="acs phenol"/><ref name="Franck"/>
:{{chem2|C6H5Cl + NaOH -> C6H5OH + NaCl}}
:{{chem2|C6H5Cl + H2O -> C6H5OH + HCl}}
These methods suffer from the cost of the chlorobenzene and the need to dispose of the chloride byproduct.

====Coal pyrolysis====
Phenol is also a recoverable byproduct of [[coal]] pyrolysis.<ref name="Franck">Franck, H.-G., Stadelhofer, J.W. Industrial Aromatic Chemistry. Springer-Verlag, New York. 1988. pp. 148-155.</ref> In the [[Lummus process]], the oxidation of toluene to [[benzoic acid]] is conducted separately.