Catalytic Wall Reactor as a Tool for Isothermal Investigations in the Heterogeneously Catalyzed Oxidation of Propene to Acrolein

Abstract

The vapor phase oxidation of propene to acrolein is a highly exothermic reaction. To ensure isothermal reaction conditions, a catalytic wall reactor was used for detailed investigations on the reaction behavior on a multicomponent bismuth-molybdate oxide catalyst. The reaction temperature showed only small influence on the selectivity to acrolein, but a significant optimum at about 360 °C is observed. The results further indicate a change in the rate-determining step: while at low temperatures (<360 °C) catalyst reoxidation is rate determining, with increasing oxygen content accelerating the formation of acrolein considerably, its influence disappears at higher temperatures. Not only does water increase the selectivity to acrolein, but also, at low temperatures, it improves catalyst reoxidation remarkably. Additionally, the formation of the most important side products (acrylic acid, carbon oxides, acetaldehyde, formaldehyde, and acetic acid) was observed, depending on the reaction parameters.

A Comparative Review of Petroleum‐Based and Bio‐Based Acrolein Production

“…[23] The rate of acrolein formation increases as a result. [24,25] Also, water possibly creates new sites for propylene adsorption on the catalyst surface, thus enhancing the partial oxidation. The service life of these industrial catalysts is usually around two to five years.…”

Regime mapping and the role of the intermediate region in wall-coated microreactors

“…On the other hand, the idealized plugflow may be useful as a limiting case, and can be approached e.g. when measuring intrinsic kinetics using coated microchannels packed with inert glass spheres (Berger and Kapteijn, 2007b;Redlingshöfer et al, 2002). Nevertheless, developing flow from an inlet flat velocity profile can be easily incorporated into our analysis, remembering that the results for mass transfer in the channel are written in terms of Sherwood number and that correlations for this quantity are available as a function of both Graetz and Schmidt number.…”

Alternative Reaction Engineering Concepts in Partial Oxidations on Oxidic Catalysts

“…In partial oxidations it had been used first by Chandrasekharan and Calderbank in 1980 (32) in the oxidation of o-xylene on vanadia-titania. In the case of the oxidation of propene to acrolein, a very detailed kinetic study has been published recently by Redlingshöfer et al (33). The investigation includes data on important side reactions, particularly where the rate determining steps are altered in different temperature domains.…”