Kinetics of ethylene combustion in the synthesis of vinyl acetate over a Pd/SiO 2 catalyst

Abstract

The kinetic parameters of ethylene combustion in the presence of acetic acid, i.e., during the synthesis of vinyl acetate and in the absence of acetic acid, have been measured in the temperature range 413–453 K over Pd supported on a high surface area SiO 2 (600 m 2/g) at pressures ranging from 5.0 to 15.0 kPa of C 2H 4 and 1.0 to 10.0 kPa of O 2. CO 2 formation as a function of the partial pressures of C 2H 4 and O 2 exhibited a negative reaction order with respect to C 2H 4 and a positive order with respect to O 2. The kinetic parameters of ethylene combustion in the presence and absence of acetic acid were essentially the same, consistent with ethylene combustion being primarily responsible for CO 2 formation in the synthesis of vinyl acetate from ethylene and acetic acid over unpromoted Pd within the pressure regime investigated.