Low Temperature Partial Oxidation of Methane over Bimetallic Nickel‐f Block Element Oxide Nanocatalysts

Abstract

AbstractThe partial oxidation of methane (POM) was studied over bimetallic nickel‐f block element oxide nanocatalysts prepared by a modified sol‐gel method. They proved to be active (conversion of methane, 50–70%) at a relatively low temperatures (550 and 650 °C) and highly selective towards synthesis gas production (selectivity, H2 60–90% and CO 50–80%). The activity and selectivity depend on the surface basicity and size of the bimetallic oxide nanoparticles: lower particle size and higher basicity, enhanced activity and selectivity to synthesis gas. Catalysts reducibility seems as well to promote their activity and selectivity. The bimetallic nickel‐gadolinium and nickel‐thorium oxide nanocatalysts proved to be more active and selective towards synthesis gas production than a commercial platinum supported catalyst (5 wt% Pt/Al2O3) or other bimetallic nickel oxide catalysts obtained by a different high temperature preparation route, which stresses the advantage of the preparation method. The bimetallic nickel‐f block element oxide nanocatalysts present also remarkable long‐term stability and an unusual low deposition of carbon, which is a major advantage, especially when compared to other nickel‐based catalysts reported for POM. Such a behavior was attributed to the lanthanide or actinide oxide phases that appear to play an important role on the catalysts stability.magnified image