Catalytic deamination on solid surfaces. Part 1.—Kinetic studies by stopped-flow gas chromatography
Abstract
Stopped-flow gas chromatography was used to study the detailed kinetics of formation of unsaturated hydrocarbons by deamination on aluminium oxide and on porous glass of aminocyclohexane, 2-aminopropane, 1-aminobutane, 2-aminobutane, 1-amino-2-methylpropane and 2-amino-2-methylpropane. The results are consistent with a proposed mechanism in which the reacting amine is rapidly adsorbed on two or three kinds of active sites of aluminium oxide or porous glass, respectively, leading to unsaturated hydrocarbons through the formation of an intermediate adsorbed product on each site. Based on this mechanism, theoretical equations are derived which adequately describe the experimental reaction rate as a function of time. Analysis of the data by means of these equations permits the calculation of the various rate constants for the surface processes. True activation energies and frequency factors for the deamination of aminocyclohexane on aluminium oxide have also been determined.