Collect. Czech. Chem. Commun. 1979, 44, 1590-1607

Kinetic analysis of coupled gas phase oxidation reaction of secondary alcohols on iridium

Pavel Slouka and Ludvík Beránek

Institute of Chemical Process Fundamentals, Czechoslovak Academy of Sciences, 165 02 Prague 6-Suchdol


Kinetics of partial gas phase oxidation of 2-butanol (B) and 4-methyl-2-pentanol (M) to ketones on Ir/C catalyst at 150 °C has been studied. In single reactions alcohol B was 4-7times more reactive than alcohol M, in competitive reactions the latter was twice as reactive as the former. Separate treatment of rate data for single and competitive reactions of both alcohols showed that each set could be described by nearly the same set of equations on 99% confidence level, including, of course, very different kinetic models. Confrontation of the kinetics of single and competitive reactions (comparison of the values of corresponding constants of rate equations) and the analysis of relative reactivities revealed the unfitness of Langmuir-Hinshelwood and redox models in this case. A model taking into account nonhomogeneity of the surface and a model derived on the basis of a chain mechanism would be able to describe better and in consistent way the kinetics of single and competitive reactions as well as the observed inversion of the reactivity of studied alcohols.