Oxygen permeation versus catalytic properties of bismuth-based oxide ion conductors used for propene oxidation in a catalytic dense membrane reactor

Dense membranes of Bi2O3–25% Er2O3 (BE25), BE25–Ag cermet, and Bi2V0.9Co0.1O5.35 (BICOVOX.10) were used to separate the two compartments of the so-called catalytic dense membrane reactor. The setup allows to measure the rate of permeation of dioxygen as well as the catalytic properties in oxidation of hydrocarbons. Higher oxygen permeation rates are observed on BE25 and BE25–Ag cermet than on BICOVOX.10 whereas the latter is more active for propene oxidation. The polarization of the membrane measured in situ during catalytic reaction shows that the overall oxygen transfer in BICOVOX.10 is enhanced and that permeation of dioxygen is not a key property in selective oxidation of hydrocarbons.