The perovskite type oxide LaNiO3 was used as starting material for the CO2 reforming of methane. The reaction was studied by a pulse technique using a CH4/CO2 ratio close to one, in order to understand the catalyst behavior. LaNiO3 was reduced prior to the reaction by temperature programmed reduction (TPR) under hydrogen. The catalyst was thus composed of La2O3 and Ni0. We have shown that good catalytic performances were obtained at 700°C and 800°C. At 800°C all the CH4 was transformed whereas the CO2 conversion reached 92% with a H2/CO ratio equal to 0.91. The crystallographic phases present after catalyst stabilization by the reaction depends on the reaction temperature. At 800°C the only phases present are La2O3 and metallic nickel whereas at 700°C the spinel phase La2NiO4 was identified leading to the conclusion that the CO2 reforming of CH4 involve consecutive reactions occurring simultaneously in our experimental conditions: Ni0+La2O3+CO2↔CO+La2 NiO4andCH4+La2NiO4→CO+2H2 +La2O3+Ni0.
|Número de páginas||9|
|Publicación||Applied Catalysis A: General|
|Estado||Publicada - 8 ago. 2003|
|Publicado de forma externa||Sí|