Effect of the nature of rhodium catalyst supports on initiation of H _2 production during n-butane oxidative reforming at room temperature

摘要

Three rhodium catalysts supported on rare earth oxides with redox properties, Rh/CeO _2, Rh/Pr _6O _(11), and Rh/Tb _4O _7, were tested for their ability to trigger oxidative reforming of n-butane at room temperature. Only Rh/CeO _2 triggered the oxidative reforming, owing to the heat generated by the spontaneous oxidation of the CeO _(2-x) species produced by prior reduction of the supported catalyst with H _2. Although the three rare earth oxides were reduced to CeO _(1.91), Pr _2O _3, and Tb _2O _3, respectively, by H _2 at ≥873 K, CeO _(1.91) was the only reduced oxide that was oxidized upon exposure to O _2 at room temperature. These results indicate that the ability of the reduced oxide support to undergo oxidation at room temperature was crucial for triggering oxidative reforming of n-butane at room temperature.