Catalytic decomposition of formic acid on oxide catalysts -: an impulse-oscillation model approach to the unimolecular mechanism

An impulse-oscillation model (IOM) was used for a time description of catalytic acts in the reactions of catalytic decomposition of formic acid on oxide catalysts. The results of computation using the model show that for the dehydrogenation reaction the most important modes are the OCO bending in bidentate adsorbed formate ion and OH stretching on the catalyst surface while for the dehydration the asymmetric stretching OCO mode in the monodentate adsorbed formate ion and metal-oxygen stretching mode on oxide catalysts. These findings confirm the results obtained [R. Larsson, M,H. Jamroz, M.A. Borowiak, J. Mel. Catal. A: Chem. 129 (1998) 41] in our previous analysis of the SET model. Assuming the synchronization of eight vibrators to be important in the reactions system considered in the present paper, the IOM method predicted ranges of wavenumbers which are close to those wavenumbers found starting from the idea of a stepwise variation of activation energies. The best ranges for the dehydrogenation reaction are proposed. (C) 1999 Published by Elsevier Science B.V. All rights reserved.