AbstractThe catalytic air oxidation of propylene to acrolein over a supported copper oxide catalyst was investigated in a continuous stirred vessel reactor between 375° and 450°C at atmospheric pressure. The effect of temperature, ratio of oxygen to propylene in feed and total feed rate (or contact time) on the conversion of propylene and the yield of acrolein were determined. It was found that with an increase in temperature, ratio of oxygen to propylene and contact time, the yield drops considerably though conversion increases.A study of the mixing characteristics of the stirred vessel reactor was carried out by following the conversion at various stirrer speeds.The kinetic data obtained were tested to determine the most probable model by the Hougen‐Watson method. The model that satisfactorily correlated the data describes the rate‐controlling step as the surface reaction occurring between adsorbed propylene, a vacant site and oxygen in the gas phase. The following Hougen‐Watson type rate equation has been proposed\documentclass{article}\pagestyle{empty}\begin{document} r = \frac{{aK_{{\rm C}3} {\rm H}_6 P_{{\rm C}_3 {\rm H}_6 {\rm P}_{{\rm O}_{\rm 2} } } }}{{(1 + K_{{\rm C}_3 {\rm H}_6 } P_{{\rm C}_3 {\rm H}_6 } + {\rm K}_{{\rm C}_3 {\rm H}_4 {\rm O}} P_{{\rm C}_3 {\rm H}_4 {\rm O}})^2 }} \end{document}The constants in the rate equation have been expressed as a function of temp