Cumene process: Difference between revisions

Content deleted Content added

Inline

Latest revision as of 22:53, 13 December 2024

First stage of Hock process: alkylation of benzene with propylene.

Second stage of Hock process: autoxidation of cumene.

The cumene process (cumene-phenol process, Hock process) is an industrial process for synthesizing phenol and acetone from benzene and propylene. The term stems from cumene (isopropyl benzene), the intermediate material during the process. It was invented by R. Ūdris and P. Sergeyev in 1942 (USSR),^[1] and independently by Heinrich Hock in 1944.^[2]^[3]

This process converts two relatively cheap starting materials, benzene and propylene, into two more valuable ones, phenol and acetone. Other reactants required are oxygen from air and small amounts of a radical initiator. Most of the worldwide production of phenol and acetone is now based on this method. In 2022, nearly 10.8 million tonnes of phenol was produced by the cumene process.^[4] In order for this process to be economical, there must also be demand for the acetone by-product as well as the phenol.^[5]

Steps of the process

Cumene is formed in the gas-phase Friedel–Crafts alkylation of benzene by propene. Benzene and propene are compressed together to a pressure of 30 standard atmospheres at 250 °C in presence of a catalytic Lewis acid. Phosphoric acid is often favored over aluminium halides. Cumene is oxidized in air, which removes the tertiary benzylic hydrogen from cumene and hence forms a cumene radical:

The cumene radical then bonds with an oxygen molecule to give cumene peroxide radical, which in turn forms cumene hydroperoxide (C₆H₅C(CH₃)₂O₂H) by abstracting a benzylic hydrogen from another cumene molecule. This latter cumene converts into cumene radical and feeds back into subsequent chain formations of cumene hydroperoxides. A pressure of 5 atm is used to ensure that the unstable peroxide is kept in liquid state.

Cumene hydroperoxide undergoes a rearrangement reaction in an acidic medium (the Hock rearrangement) to give phenol and acetone. In the first step, the terminal hydroperoxy oxygen atom is protonated. This is followed by a step in which the phenyl group migrates from the benzyl carbon to the adjacent oxygen and a water molecule is lost, producing a resonance stabilized tertiary carbocation. The concerted mechanism of this step is similar to the mechanisms of the Baeyer–Villiger oxidation^[6] and Criegee rearrangement reactions, and also the oxidation step of the hydroboration–oxidation process.^[7] In 2009, an acidified bentonite clay was proven to be a more economical catalyst than sulfuric acid as the acid medium.

The resulting carbocation is then attacked by water, forming a hemiacetal-like structure. After transfer of a proton from the hydroxy oxygen to the ether oxygen, the ion falls apart into phenol and acetone.

Related reactions and modifications

Alternatives to acetone co-production

Cyclohexylbenzene can replace isopropylbenzene. Via the Hock rearrangement, cyclohexylbenzene hydroperoxide cleaves to give phenol and cyclohexanone. Cyclohexanone is an important precursor to some nylons.^[8]

Starting with the alkylation of benzene with mixture of 1 and 2-butenes, the cumene process produces phenol and butanones.^[5]

Alternatives to phenol production

Hydroquinone is prepared by dialkylation of benzene with propene to give 1,4-diisopropylbenzene. This compound reacts with air to afford the bis(hydroperoxide). Analogous to the behavior of cumene hydroperoxide, it rearranges in acid to give acetone and hydroquinone. Oxidation of hydroquinone gives 1,4-benzoquinone:^[9]
${\ce {C6H4(CHMe2)2 + 2 1/2 O2 -> C6H4O2 + 2 OCMe2 + H2O}}$
Resorcinol is analogously prepared by converting 1,3-Diisopropylbenzene into the bis(hydroperoxide), which fragments to resorcinol and acetone.^[10]
2-Naphthol can also be produced by a method analogous to the cumene process.^[11]
3-Chlorophenol, which does not arise by chlorination of phenol, can be produced by cumene process beginning with the alkylation of chlorobenzene with propylene.^[12]
Cresols are produced from isopropyltoluene.^[13]

Acetone processing

Crude acetone is hydrogenated in the liquid phase over Raney nickel or a mixture of copper and chromium oxide to give isopropyl alcohol. This process is useful, when it is coupled with excess acetone production.^[14] Mitsui & Co. developed additional step(s) to hydrogenating acetone and dehydrating the isopropanol product to propene, which is recycled as a starting reactant.^[5]

Byproducts

Byproducts of the cumene process to produce phenol and acetone are acetophenone and alpha-methylstyrene.

References

^ "Latvian". Archived from the original on 2016-03-03. Retrieved 2011-02-27.
^ Hock, H. and Lang, S. (1944), Autoxydation von Kohlenwasserstoffen, IX. Mitteil.: Über Peroxyde von Benzol-Derivaten. Berichte der deutschen chemischen Gesellschaft (A and B Series), 77: 257–264 doi:10.1002/cber.19440770321
^ Concise Encyclopedia Chemistry (1993) Mary Eagleso
^ "Phenol Market Size, Share, Analysis & Forecast, 2035 – ChemAnalyst". ChemAnalyst. Retrieved 2024-04-09.
^ ^a ^b ^c "Direct Routes to Phenol". Archived from the original on 2007-04-09. Retrieved 2006-12-26.
^ Streitwieser, A; Heathcock, C.H. (1992). "30". Introduction to Organic Chemistry. Kosower, E.M. (4th ed.). New York: MacMillan. pp. 1018. ISBN 0-02-418170-6.
^ K.P.C., Vollhardt; N.E. Schore (2003). "22". Organic Chemistry: Structure and Function (4th ed.). New York: Freeman. p. 988. ISBN 0-7167-4374-4.
^ Plotkin, Jeffrey S. (2016-03-21). "What's New in Phenol Production?". American Chemical Society. Archived from the original on 2019-10-27. Retrieved 2018-01-02.
^ Gerhard Franz, Roger A. Sheldon "Oxidation" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2000 doi:10.1002/14356007.a18_261
^ K. W. Schmiedel; D. Decker (2012). "Resorcinol". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a23_111.pub2. ISBN 978-3527306732.
^ Gerald Booth "Naphthalene Derivatives" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim. doi:10.1002/14356007.a17_009.
^ François Muller; Liliane Caillard (2011). "Chlorophenols". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a07_001.pub2. ISBN 978-3527306732.
^ Roger A. Sheldon (1983). "Synthesis and uses of alkyl hydroperoxides and dialkyl peroxides". In Patai, Saul (ed.). Syntheses and Uses of Hydroperoxides and Dialkylperoxides. PATAI'S Chemistry of Functional Groups. John Wiley & Sons. pp. 161–200. doi:10.1002/9780470771730.ch6. ISBN 978-0-471-10218-2.
^ Papa, A. J. "Propanols". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a22_173. ISBN 978-3527306732.

External links

Phenol -- The essential chemical industry online

[1] "Latvian". Archived from the original on 2016-03-03. Retrieved 2011-02-27.

[2] Hock, H. and Lang, S. (1944), Autoxydation von Kohlenwasserstoffen, IX. Mitteil.: Über Peroxyde von Benzol-Derivaten. Berichte der deutschen chemischen Gesellschaft (A and B Series), 77: 257–264 doi:10.1002/cber.19440770321

[3] Concise Encyclopedia Chemistry (1993) Mary Eagleso

[4] "Phenol Market Size, Share, Analysis & Forecast, 2035 – ChemAnalyst". ChemAnalyst. Retrieved 2024-04-09.

[Plotkin2006-5] "Direct Routes to Phenol". Archived from the original on 2007-04-09. Retrieved 2006-12-26.

[6] Streitwieser, A; Heathcock, C.H. (1992). "30". Introduction to Organic Chemistry. Kosower, E.M. (4th ed.). New York: MacMillan. pp. 1018. ISBN 0-02-418170-6.

[7] K.P.C., Vollhardt; N.E. Schore (2003). "22". Organic Chemistry: Structure and Function (4th ed.). New York: Freeman. p. 988. ISBN 0-7167-4374-4.

[acs_phenol-8] Plotkin, Jeffrey S. (2016-03-21). "What's New in Phenol Production?". American Chemical Society. Archived from the original on 2019-10-27. Retrieved 2018-01-02.

[9] Gerhard Franz, Roger A. Sheldon "Oxidation" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2000 doi:10.1002/14356007.a18_261

[10] K. W. Schmiedel; D. Decker (2012). "Resorcinol". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a23_111.pub2. ISBN 978-3527306732.

[Ullmann2005-11] Gerald Booth "Naphthalene Derivatives" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim. doi:10.1002/14356007.a17_009.

[12] François Muller; Liliane Caillard (2011). "Chlorophenols". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a07_001.pub2. ISBN 978-3527306732.

[Patai-13] Roger A. Sheldon (1983). "Synthesis and uses of alkyl hydroperoxides and dialkyl peroxides". In Patai, Saul (ed.). Syntheses and Uses of Hydroperoxides and Dialkylperoxides. PATAI'S Chemistry of Functional Groups. John Wiley & Sons. pp. 161–200. doi:10.1002/9780470771730.ch6. ISBN 978-0-471-10218-2.

[Ullmann-14] Papa, A. J. "Propanols". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a22_173. ISBN 978-3527306732.

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]

[12]

[13]

[14]

@@ Line 1: / Line 1: @@
+{{Short description|Industrial process}}
-The '''cumene process''' ('''cumene-phenol process''', '''Hock process''') is an [[industrial process]] for synthesizing [[phenol]] and [[acetone]] from [[benzene]] and [[propylene]]. The term stems from [[cumene]] (isopropyl benzene), the intermediate material during the process. It was invented by R. Ūdris and P. Sergeyev in 1942 (USSR).<ref>http://izgudrojumi.lza.lv/izg_en.php?id=54</ref>, and independently by Heinrich Hock in 1944<ref>Hock, H. and Lang, S. (1944), Autoxydation von Kohlenwasserstoffen, IX. Mitteil.: Über Peroxyde von Benzol-Derivaten. [[Berichte der deutschen chemischen Gesellschaft]] (A and B Series), 77: 257–264 {{doi|10.1002/cber.19440770321}}</ref><ref>''Concise Encyclopedia Chemistry'' (1993) Mary Eagleso</ref>
+[[File:Propylene+C6H6.svg|344px|thumb|right|First stage of Hock process: alkylation of benzene with propylene.]]
+[[File:Hockpart2.svg|thumb|344px|right|Second stage of Hock process: [[autoxidation]] of cumene.]]
+The '''cumene process''' ('''cumene-phenol process''', '''Hock process''') is an [[industrial process]] for synthesizing [[phenol]] and [[acetone]] from [[benzene]] and [[propylene]]. The term stems from [[cumene]] (isopropyl benzene), the intermediate material during the process. It was invented by R. Ūdris and P. Sergeyev in 1942 (USSR),<ref>{{Cite web|url=http://izgudrojumi.lza.lv/izg_en.php?id=54|title=Latvian|access-date=2011-02-27|archive-date=2016-03-03|archive-url=https://web.archive.org/web/20160303201522/http://izgudrojumi.lza.lv/izg_en.php?id=54|url-status=dead}}</ref> and independently by Heinrich Hock in 1944.<ref>Hock, H. and Lang, S. (1944), Autoxydation von Kohlenwasserstoffen, IX. Mitteil.: Über Peroxyde von Benzol-Derivaten. [[Berichte der deutschen chemischen Gesellschaft]] (A and B Series), 77: 257–264 {{doi|10.1002/cber.19440770321}}</ref><ref>''Concise Encyclopedia Chemistry'' (1993) Mary Eagleso</ref>
-This process converts two relatively cheap starting materials, [[benzene]] and [[propylene]], into two more valuable ones, [[phenol]] and [[acetone]]. Other reactants required are [[oxygen]] from air and small amounts of a [[radical initiator]]. Most of the worldwide production of phenol and [[acetone]] is now based on this method. In 2003, nearly 7 million tonnes of phenol was produced by the cumene process.<ref name="Ullmann2004">Manfred Weber, Markus Weber, Michael Kleine-Boymann "Phenol" in Ullmann's Encyclopedia of Industrial Chemistry 2004, Wiley-VCH. {{DOI|10.1002/14356007.a19_299.pub2}}.</ref> In order for this process to be economical, there must also be demand for the [[acetone]] by-product as well as the [[phenol]].<ref name=cumeneprocess>{{Cite web |url=http://www.chemistry.org/portal/a/c/s/1/feature_pro.html?id=c373e908e6e847ac8f6a17245d830100 |title=Direct Routes to Phenol |access-date=2006-12-26 |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 |url-status=dead }}</ref>
+This process converts two relatively cheap starting materials, [[benzene]] and [[propylene]], into two more valuable ones, [[phenol]] and [[acetone]]. Other reactants required are [[oxygen]] from air and small amounts of a [[radical initiator]]. Most of the worldwide production of phenol and [[acetone]] is now based on this method. In 2022, nearly 10.8 million tonnes of phenol was produced by the cumene process.<ref>{{cite web | title=Phenol Market Size, Share, Analysis & Forecast, 2035 – ChemAnalyst | website=ChemAnalyst | url=https://www.chemanalyst.com/industry-report/phenol-market-184 | access-date=2024-04-09}}</ref> In order for this process to be economical, there must also be demand for the [[acetone]] by-product as well as the [[phenol]].<ref name=Plotkin2006>{{Cite web |url=http://www.chemistry.org/portal/a/c/s/1/feature_pro.html?id=c373e908e6e847ac8f6a17245d830100 |title=Direct Routes to Phenol |access-date=2006-12-26 |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 |url-status=dead }}</ref>
-[[Image:Cumene-process-overview-2D-skeletal V2.svg|500px|center|Overview of the cumene process]]
 ==Steps of the process==
-Cumene is formed in the gas-phase [[Friedel–Crafts reaction#Friedel–Crafts alkylation|Friedel–Crafts alkylation]] of benzene by propylene. Benzene and propylene are compressed together to a pressure of 30 [[Atmospheric pressure|standard atmospheres]] at 250 °C (482 °F) in presence of a [[catalyst|catalytic]] [[Lewis acid]]. [[Phosphoric acid]] is often favored over [[aluminium]] [[halide]]s. Cumene is oxidized in air, which removes the tertiary [[benzyl]]ic hydrogen from cumene and hence forms a cumene [[radical (chemistry)|radical]]:
+Cumene is formed in the gas-phase [[Friedel–Crafts reaction#With alkenes|Friedel–Crafts alkylation]] of benzene by propene. Benzene and propene are compressed together to a pressure of 30 [[Atmospheric pressure|standard atmospheres]] at 250&nbsp;°C in presence of a [[catalyst|catalytic]] [[Lewis acid]]. [[Phosphoric acid]] is often favored over [[aluminium]] [[halide]]s. Cumene is oxidized in air, which removes the tertiary [[benzyl]]ic hydrogen from cumene and hence forms a cumene [[radical (chemistry)|radical]]:
-[[Image:Cumene-radical-formation-2D-skeletal V2.svg|300px|center]]
+::[[Image:Cumene-radical-formation-2D-skeletal V2.svg|300px]]
-The cumene radical then [[chemical bond|bonds]] with an oxygen molecule to give cumene [[peroxide]] radical, which in turn forms [[cumene hydroperoxide]] (C<sub>6</sub>H<sub>5</sub>C(CH<sub>3</sub>)<sub>2</sub>-O-O-H) by abstracting a benzylic hydrogen from another cumene molecule. This latter cumene converts into cumene radical and feeds back into subsequent chain formations of cumene hydroperoxides. A pressure of 5 [[Atmosphere (unit)|atm]] is used to ensure that the unstable peroxide is kept in liquid state.
+The cumene radical then [[chemical bond|bonds]] with an oxygen molecule to give cumene [[peroxide]] radical, which in turn forms [[cumene hydroperoxide]] (C<sub>6</sub>H<sub>5</sub>C(CH<sub>3</sub>)<sub>2</sub>O<sub>2</sub>H) by abstracting a benzylic hydrogen from another cumene molecule. This latter cumene converts into cumene radical and feeds back into subsequent chain formations of cumene hydroperoxides. A pressure of 5 [[Atmosphere (unit)|atm]] is used to ensure that the unstable peroxide is kept in liquid state.
-[[Image:Cumene-peroxide-radical-formation-2D-skeletal.svg|300px|center]]
+::[[Image:Cumene-peroxide-radical-formation-2D-skeletal.svg|300px]]
-[[Image:Cumene-hydroperoxide-formation-2D-skeletal.svg|450px|center]]
+::[[Image:Cumene-hydroperoxide-formation-2D-skeletal.svg|450px]]
-Cumene hydroperoxide is then [[Hydrolysis|hydrolysed]] in an [[acid]]ic medium (the '''Hock rearrangement''') to give [[phenol]] and [[acetone]]. In the first step, the terminal hydroperoxy oxygen atom is protonated. This is followed by a step in which the phenyl group migrates from the benzyl carbon to the adjacent oxygen and a water molecule is lost, producing a [[resonance (chemistry)|resonance]] stabilized tertiary [[carbocation]]. The concerted mechanism of this step is similar to the mechanisms of the [[Baeyer–Villiger oxidation]]<ref>{{cite book|last=Streitwieser|first=A|author2=Heathcock, C.H.|others=Kosower, E.M.|title=Introduction to Organic Chemistry|publisher=MacMillan|location=New York|year=1992|edition=4th|pages=[https://archive.org/details/introductiontoor00stre_0/page/1018 1018]|chapter=30|isbn=0-02-418170-6|url=https://archive.org/details/introductiontoor00stre_0/page/1018}}</ref> and also the oxidation step of [[Hydroboration-oxidation#Hydroboration–oxidation|hydroboration-oxidation]].<ref>{{cite book|last=K.P.C.|first=Vollhardt|author2=N.E. Schore|authorlink2=Neil E. Schore|title=Organic Chemistry: Structure and Function|publisher=Freeman|location=New York|year=2003|edition=4th|pages=[https://archive.org/details/organicchemistry00voll_0/page/988 988]|chapter=22|isbn=0-7167-4374-4|url=https://archive.org/details/organicchemistry00voll_0/page/988}}</ref>
+Cumene hydroperoxide undergoes a [[rearrangement reaction]] in an [[acid]]ic medium (the '''Hock rearrangement''') to give [[phenol]] and [[acetone]]. In the first step, the terminal hydroperoxy oxygen atom is protonated. This is followed by a step in which the phenyl group migrates from the benzyl carbon to the adjacent oxygen and a water molecule is lost, producing a [[resonance (chemistry)|resonance]] stabilized tertiary [[carbocation]]. The concerted mechanism of this step is similar to the mechanisms of the [[Baeyer–Villiger oxidation]]<ref>{{cite book|last=Streitwieser|first=A|author2=Heathcock, C.H.|others=Kosower, E.M.|title=Introduction to Organic Chemistry|publisher=MacMillan|location=New York|year=1992|edition=4th|pages=[https://archive.org/details/introductiontoor00stre_0/page/1018 1018]|chapter=30|isbn=0-02-418170-6|chapter-url=https://archive.org/details/introductiontoor00stre_0/page/1018}}</ref> and [[Criegee rearrangement]] reactions, and also the oxidation step of the [[Hydroboration–oxidation reaction#Hydroboration–oxidation|hydroboration–oxidation]] process.<ref>{{cite book|last=K.P.C.|first=Vollhardt|author2=N.E. Schore|authorlink2=Neil E. Schore|title=Organic Chemistry: Structure and Function|publisher=Freeman|location=New York|year=2003|edition=4th|chapter-url=https://archive.org/details/organicchemistry00voll_0/page/988 |page=988|chapter=22|isbn=0-7167-4374-4}}</ref>
-In 2009, an acidified [[bentonite]] clay was proven to be a more economical catalyst than sulfuric acid as the acid medium.
+In 2009, an acidified [[bentonite]] clay was proven to be a more economical catalyst than [[sulfuric acid]] as the acid medium.
-[[Image:Cumene-process-phenyl-migration-2D-skeletal V2.svg|450px|center]]
+::[[Image:Cumene-process-phenyl-migration-2D-skeletal V2.svg|450px]]
+The resulting [[carbocation]] is then attacked by water, forming a [[hemiacetal]]-like structure. After transfer of a proton from the hydroxy oxygen to the ether oxygen, the ion falls apart into phenol and acetone.
+::[[Image:Cumene-process-final-steps-2D-skeletal.svg|600px]]
-As shown below, the resulting [[carbocation]] is then attacked by water, a proton is then transferred from the hydroxy oxygen to the ether oxygen, and finally the ion falls apart into phenol and acetone.
+==Related reactions and modifications==
-[[Image:Cumene-process-final-steps-2D-skeletal.svg|600px|center]]
+===Alternatives to acetone co-production===
+[[Cyclohexylbenzene]] can replace isopropylbenzene. Via the Hock rearrangement, cyclohexylbenzene hydroperoxide cleaves to give phenol and [[cyclohexanone]]. Cyclohexanone is an important precursor to some [[nylon]]s.<ref name="acs phenol">{{cite web |url=https://www.acs.org/content/acs/en/pressroom/cutting-edge-chemistry/what-s-new-in-phenol-production-.html |title=What's New in Phenol Production? |last=Plotkin |first=Jeffrey S. |publisher=American Chemical Society |date=2016-03-21 |access-date=2018-01-02 |archive-url=https://web.archive.org/web/20191027122212/https://www.acs.org/content/acs/en/pressroom/cutting-edge-chemistry/what-s-new-in-phenol-production-.html |archive-date=2019-10-27 |url-status=dead }}</ref>
+Starting with the alkylation of benzene with mixture of [[1-Butene|1]] and [[2-Butene|2-butenes]], the cumene process produces phenol and [[butanone]]s.<ref name=Plotkin2006/>
-==Alternatives to acetone co-production==
-[[Cyclohexylbenzene]] can replace isopropylbenzene. Via the Hock rearrangement, cyclohexylbenzene hydroperoxide cleaves to give phenol and [[cyclohexanone]]. Cyclohexanone is an important precursor to some [[nylon]]s.<ref name="acs phenol">{{cite web |url=https://www.acs.org/content/acs/en/pressroom/cutting-edge-chemistry/what-s-new-in-phenol-production-.html |title=What's New in Phenol Production? |last=Plotkin |first=Jeffrey S. |publisher=American Chemical Society |date=2016-03-21 |access-date=2018-01-02}}</ref>
+===Alternatives to phenol production===
-Starting with the alkylation of benzene with mixture of [[1-Butene|1]] and [[2-Butene|2-butenes]], the cumene process produces phenol and [[butanone]]s.<ref name=cumeneprocess/>
+*[[Hydroquinone]] is prepared by dialkylation of benzene with propene to give [[Diisopropylbenzenes|1,4-diisopropylbenzene]]. This compound reacts with air to afford the bis(hydroperoxide).  Analogous to the behavior of [[cumene hydroperoxide]], it rearranges in acid to give [[acetone]] and hydroquinone. Oxidation of hydroquinone gives 1,4-benzoquinone:<ref>Gerhard Franz, Roger A. Sheldon "Oxidation" in ''Ullmann's Encyclopedia of Industrial Chemistry'', Wiley-VCH, Weinheim, 2000 {{doi|10.1002/14356007.a18_261}}</ref>
+*:<chem>C6H4(CHMe2)2 + 2 1/2 O2 -> C6H4O2 + 2 OCMe2 + H2O</chem>
+*[[Resorcinol]] is analogously prepared by converting [[1,3-Diisopropylbenzene]] into the bis(hydroperoxide), which fragments to resorcinol and acetone.<ref>{{Ullmann |title=Resorcinol|author1=K. W. Schmiedel |author2=D. Decker |doi=10.1002/14356007.a23_111.pub2|year=2012}}</ref>
+*[[2-Naphthol]] can also be produced by a method analogous to the cumene process.<ref name=Ullmann2005>Gerald Booth "Naphthalene Derivatives" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim. {{doi|10.1002/14356007.a17_009}}.</ref>
+*[[3-Chlorophenol]], which does not arise by chlorination of phenol, can be produced by cumene process beginning with the alkylation of chlorobenzene with propylene.<ref>{{Ullmann|author1=François Muller |author2=Liliane Caillard |title=Chlorophenols |year=2011 |doi=10.1002/14356007.a07_001.pub2}}</ref>
+*[[Cresol]]s are produced from isopropyltoluene.<ref name=Patai>{{cite book |title=Syntheses and Uses of Hydroperoxides and Dialkylperoxides |editor1-first=Saul |editor1-last=Patai |author=Roger A. Sheldon |chapter=Synthesis and uses of alkyl hydroperoxides and dialkyl peroxides |year=1983 |publisher=John Wiley & Sons |doi=10.1002/9780470771730.ch6 |series=PATAI'S Chemistry of Functional Groups|pages=161–200 |isbn=978-0-471-10218-2 }}</ref>
+===Acetone processing===
-==Alternatives to phenol production==
+Crude acetone is hydrogenated in the liquid phase over [[Raney nickel]] or a mixture of copper and chromium oxide to give [[isopropyl alcohol]]. This process is useful, when it is coupled with excess acetone production.<ref name=Ullmann>{{Ullmann |author=Papa, A. J. |title=Propanols |doi=10.1002/14356007.a22_173}}</ref>
-*[[Hydroquinone]] is prepared by dialkylation of benzene with propene to give [[Diisopropylbenzenes|1,4-diisopropylbenzene]]. This compound reacts with air to afford the bis(hydroperoxide).  Analogous to the behavior of [[cumene hydroperoxide]], it rearranges in acid to give [[acetone]] and hydroquinone. Oxidation of hydroquinone gives 1,4-benzoquinone:<ref>Gerhard Franz, Roger A. Sheldon "Oxidation" in ''Ullmann's Encyclopedia of Industrial Chemistry'', Wiley-VCH, Weinheim, 2000 {{DOI|10.1002/14356007.a18_261}}</ref>
+[[Mitsui & Co.]] developed additional step(s) to [[hydrogenation|hydrogenating]] acetone and dehydrating the [[isopropanol]] product to propene, which is recycled as a starting reactant.<ref name=Plotkin2006/>
-:C<sub>6</sub>H<sub>4</sub>(CHMe<sub>2</sub>)<sub>2</sub>  +  2.5 O<sub>2</sub>   →   C<sub>6</sub>H<sub>4</sub>O<sub>2</sub>  +  2 OCMe<sub>2</sub>  +  H<sub>2</sub>O
-*[[Resorcinol]] is analogously prepared by converting [[1,3-Diisopropylbenzene]] into the bis(hydroperoxide), which fragments to resorcinol and acetone.<ref name="resorcinol">{{cite web |title=Resorcinol |url=https://toxnet.nlm.nih.gov/cgi-bin/sis/search2/r?dbs+hsdb:@term+@rn+@rel+108-46-3 |website=Toxnet |publisher=U.S. National Library of Medicine |accessdate=10 October 2019}}</ref>
-*[[2-Naphthol]] can also be produced by a method analogous to the cumene process.<ref name=Ullmann2005>Gerald Booth "Naphthalene Derivatives" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim. {{DOI|10.1002/14356007.a17_009}}.</ref>
-*[[3-Chlorophenol]], which does not arise by chlorination of phenol, can be produced by Cumene process beginning with the alkylation of chlorobenzene with propylene.<ref>{{Ullmann|authors=François Muller, Liliane Caillard|title=Chlorophenols|year=2011|doi=10.1002/14356007.a07_001.pub2}}</ref>
+===Byproducts===
-==Acetone processing==
-Crude acetone is hydrogenated in the liquid phase over [[Raney nickel]] or a mixture of copper and chromium oxide to give [[isopropyl alcohol]]. This process is useful, when it is coupled with excess acetone production.<ref name = Ullmann>{{Ullmann | author = Papa, A. J. | title = Propanols | doi = 10.1002/14356007.a22_173}}</ref>[https://en.wikipedia.org/enwiki/w/index.php?title=Isopropyl_alcohol&oldid=947438308]
+Byproducts of the cumene process to produce phenol and acetone are [[acetophenone]] and [[alpha-methylstyrene]].
-[[Mitsui & Co.]] developed additional step(s) to [[hydrogenation|hydrogenating]] the acetone product and [[dehydration|dehydrating]] the [[isopropanol]] product to propene, which is recycled as a starting reactant.
 ==See also==
 * [[Bisphenol A]]
-* [[Dow process]]
+* [[Dow process (phenol)]]
 * [[Friedel Crafts alkylation]]
 * [[Baeyer–Villiger oxidation]]
@@ Line 52: / Line 60: @@
 [[Category:Chemical processes]]
+[[Category:Soviet inventions]]