Scrutinizing different catalytic processes in the (Gd-La) codoped CeO2-NiO-carbonate membrane reactor, implying CO2 mechanisms

In recent years, new and novel ceramic carbonate membrane reactors have received attention due to their high capabilities. Within this context, a membrane reactor system implies a gas permeation combined with a catalytic reaction process, resulting in a synergetic effect of a bifunctional material, which intensifies the whole process. This work presents the use of a (Gd-La) codoped CeO2-NiO-carbonate membrane reactor, for two different processes; i) carbon monoxide (CO) oxidation and ii) dry methane (CH4) reforming, in which carbon dioxide (CO2) permeation is needed. The (Gd-La) codoped CeO2-NiO powder was obtained by the so called one-pot method, obtaining a Gd-La codoped ceria and nickel oxide mixture, determined by X-ray diffraction and high resolution transmission electron microscopy. In any case, the formation of these phases probed to possess a better CO2 permeation than that obtained when a mechanical mixture of Ce0.85Gd0.15O2-delta and LaNiO3 was evaluated. This membrane reactor showed efficient CO oxidation and CO2 permeation yields, which were highly improved through the oxygen (O2) addition in the feed and/or sweep membrane sides. In the dry CH4 reforming reaction, this composition was able to perform the reaction, although it was importantly improved by a catalyst addition (LaNiO3) being the CO2 permeation the limiting step of the whole reaction process.

Automated summary

The study investigates the use of (Gd-La) co-doped CeO2-NiO-carbonate membrane reactor for CO oxidation and CH4 dry reforming, demonstrating better CO2 permeation performance compared to a mechanical mixture of materials. The addition of oxygen in the feed and membrane sides improves CO2 permeation yields, while in the CH4 reforming reaction, the CO2 permeation remains the limiting step despite catalyst (LaNiO3) addition.