Transient Response Study of the Ammoxidation of Propene and Propane on an Sb−V−Oxide Catalyst

Abstract

The reaction pathways in the ammoxidation of propene and of propane over an Sb-V-oxide catalyst were studied by analyzing the modes of transient responses of reactants and products resulting from step changes from inert gas to reactant feed. The pathway from propane to acrylonitrile begins with the oxidative dehydrogenation of propane to form propene. After readsorption, the propene is then transformed into adsorbed acrolein, which eventually reacts with an NH x surface species to form acrylonitrile. The adsorption of propane is rate limiting for the propane conversion, but the desorption of water formed from the propene is slow and determines the product distribution. The response modes for the direct oxidation and ammoxidation of propene are consistent with the desorption of water being rate limiting. A comparison of the experimental responses with responses simulated under the assumption that the formation of an allylic intermediate is rate determining reveals an important difference in profiles, indicating this step to not be rate determining. The results show that substantial qualitative information concerning the reaction pathways can be obtained from the analysis of transient profile modes.

Catalytic effects in propene ammoxidation achieved through substitutions in the M2 phase of the Mo–V–Nb–Te-oxide system

“…The increase of the activity being associated with the intended incorporation of Fe 3+ for V 4+ , however, seems to be linked to the Fe-site being active for burning acrolein (figure 7) without affecting the selectivity to acrylonitrile. This observation agrees with acrylonitrile, opposed to acrolein, being a relatively stable product [26].…”

Synthesis and room-temperature NO2 sensing properties of Sb2O5 nanowires

“…Sb 2 O 5 possesses a high refractive index and high abrasive resistance and is widely used as an optical material [2]. Sb 2 O 5 is a Lewis acid for catalyzing the transformation of propene into acrylonitrile [3]. Sb 2 O 5 nanoparticles have been used as polymer electrolyte fillers [2].…”

Facile catalyst-free straightforward thermal evaporation of ultra-long antimony oxide microwires: Synthesis and characterization

“…Among metal oxides antimony oxide is an important V-VI main group compound which has been widely used in industry as fire retardant, polymer fillers, flocculent in titania production catalysis for organic reactions, anode materials in lithium battery and so on [1][2][3][4][5]. It is anticipated that antimony oxide micro/nanowires will shows unique optoelectronic properties.…”