Boudouart reaction

CVD starting from zerovalent complexes such as [Fe(CO)s] and [Mo(CO)6] can be attained over a quite broad temperature range (373-673 K), but the final deposits are significantly contaminated by carbon [65, 66], presumably generated by the Boudouart reaction involving two CO and affording CO2 and C. To avoid carbon deposition oxygen can be introduced into the gas phase [67], but metal oxides are produced instead. 

Coke, deposited on a catalyst, may be removed by one of several reactions oxidation, reaction with water to form carbon monoxide and hydrogen methanation, and the Boudouart reactions. 

This effect was attributed to the ability of C02 to keep the catalyst in its intermediate oxidation state such as Cu(I) (29), or to prevent reduction of zinc oxide with concomitant formation of brass (27), or to the reversal of the Boudouart reaction... 

Carbon monoxide alone may form carbon according to the Boudouart reaction ... 

Permemann et al. performed partial oxidation of propane and identified the Boudouart reaction to be responsible for significant coke formation, which was observed in particular downstream of the catalyst on the steel surface of their microchannel test reactors [59]. The nickel contained in the stainless steel clearly served as the active species. Coating the steel with a-alumina suppressed the coke formation. 

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