Chemical kinetics assisted by a microcomputer. A study of the pyrolysis of actaldehyde

Abstract

Computational procedures of general applicability to kinetic studies are explored, which include, beyond data logging, averaging and curve fitting, some special attention to accuracy of measurement of the reaction parameter, here being the pressure. This then allows the successful use of method for the assessment of time-order of a reaction from a selected portion of the reaction growth curve. Numerical modelling in parallel with experiments is used, and the importance of the modelling of diffusion effects is underlined.

In the experimental study of the pyrolysis of acetaldehyde numerical results for initial rate and order, and overall activation energy, were different from those of other workers, but a reason for this is offered in terms of processes at the wall of the vessel. The time-order of reaction is explored at 550 °C both experimentally and in a numerical model, and as a result it is suggested that heterogeneous processes have a significant part to play, most notably in explaining the observation of initial time-orders of ca. 1.7.