{{Short description|Process for industrial production of hydrogen cyanide}} thumb|right|Diagram from 1931 showing the Andrussow process The '''Andrussow process''' is the dominant industrial process for the production of hydrogen cyanide.<ref name=Ullmann>{{ Ullmann |last1=Gail|first1=E.|last2=Gos|first2=S.|last3=Kulzer|first3=R.|last4=Lorösch |first4=J.|last5=Rubo|first5=A.|last6=Sauer|first6=M. | title = Cyano Compounds, Inorganic | doi = 10.1002/14356007.a08_159.pub2 }}</ref> It involves the reaction of methane, ammonia, and oxygen. The process is catalyzed by a platinum-rhodium alloy.<ref>{{cite journal |doi=10.1016/j.apcata.2010.03.046 |title=Mechanistic aspects of the Andrussow process over Pt-Rh gauzes. Effect of gauze morphology and oxygen coverage on primary O2–NH3–CH4 interactions |date=2010 |last1=Kondratenko |first1=V.A. |last2=Weinberg |first2=G. |last3=Pohl |first3=M.-M. |last4=Su |first4=D.S. |journal=Applied Catalysis A: General |volume=381 |issue=1–2 |pages=66–73 |bibcode=2010AppCA.381...66K }}</ref>
:2 CH<sub>4</sub> + 2 NH<sub>3</sub> + 3 O<sub>2</sub> → 2 HCN + 6 H<sub>2</sub>O
Hydrogen cyanide is highly valued for the production or acrylonitrile and adiponitrile, as well as alkali metal salts such as potassium cyanide.<ref name=Ullmann/>
==Process details== This reaction is very exothermic. The change of enthalpy of this reaction is equal to ''-481.06 kJ''.<ref>{{Citation | first=Gyula | last=Deák | title=Menné reakcie v organickej chémii|year = 1980|publisher=Vydavateľstvo technickej a ekonomickej literatúry| location = Bratislava| page = 14}}</ref> The heat provided by the main reaction serves as a catalyst for other side reactions. :CH<sub>4</sub> + H<sub>2</sub>O → CO + 3 H<sub>2</sub> :2 CH<sub>4</sub> + 3 O<sub>2</sub> → 2 CO + 4 H<sub>2</sub>O :4 NH<sub>3</sub> + 3 O<sub>2</sub> → 2 N<sub>2</sub> + 6 H<sub>2</sub>O
These side reactions can be minimized by only short exposures to the catalyst of the order of 0.0003 s.<ref>{{cite journal|last=Pirie|first=J M|title=The Manufacture of Hydrocyanic Acid by the Andrussow Process|journal=Platinum Metals Rev.|year=1958|volume=2|issue=1|pages=7–11|doi=10.1595/003214058X21711 |url=http://www.platinummetalsreview.com/pdf/pmr-v2-i1-007-011.pdf|access-date=28 March 2014|archive-date=31 January 2013|archive-url=https://web.archive.org/web/20130131122838/http://www.platinummetalsreview.com/pdf/pmr-v2-i1-007-011.pdf|url-status=dead}}</ref>
==Historical articles== The process is based on a reaction that was discovered by Leonid Andrussow in 1927. In the following years he developed the process that is named after him. HCN is also produced in the BMA process.<ref>{{cite journal | title = Über die schnell verlaufenden katalytischen Prozesse in strömenden Gasen und die Ammoniak-Oxydation (V) | author = Leonid Andrussow | journal = Berichte der Deutschen Chemischen Gesellschaft | volume = 60 | issue = 8 | pages = 2005–2018 | year = 1927 | doi = 10.1002/cber.19270600857 }}</ref><ref>{{cite journal | title = Über die katalytische Oxydation von Ammoniak-Methan-Gemischen zu Blausäure (The catalytic oxidation of ammonia-methane-mixtures to hydrogen cyanide) | author = L. Andrussow | journal = Angewandte Chemie | volume = 48 | issue = 37 | pages = 593–595 | year = 1935 | doi = 10.1002/ange.19350483702 }}</ref>
==References== {{Reflist}} {{Organic reactions}} {{DEFAULTSORT:Andrussow Oxidation}} Category:Organic redox reactions Category:Industrial processes Category:Catalysis Category:Name reactions