Methane oxidation by lattice oxygen of Ni/BaTi1−xInxO3−δ catalysts

BaTi1−xInxO3−δ perovskites (called BITx) were evaluated as supports of nickel catalysts for methane oxidation in the absence of gas-phase oxygen. Ni/BaTi1−xInxO3−δ (x = 0 and 0.3) catalysts were studied, by temperature programmed surface reaction of methane (TPSR-CH4) and pulses at 850 °C. In these conditions, the only oxygen source is the oxide bulk support. TPSR-CH4 results suggest that the support is able to oxidize the methane producing H2 and CO at temperatures above 750 °C. Ni/BT and Ni/BIT0.7 catalysts, showed a high selectivity towards partial oxidation products. Ni/BIT0.7 catalyst was more stable than Ni/BT due to the existence of Ni–In alloys which catalyze less the cracking reaction. Moreover, the higher ionic conductivity of BIT0.7 facilitates the O2− ions diffusion to the surface and promotes the oxidation of carbonaceous deposits formed on the metal–support interface preventing thus catalyst deactivation.