Comparative Study of Ni-based Mixed Oxide Catalyst for Carbon Dioxide Reforming of Methane

Abstract

Carbon dioxide reforming of methane (CDRM) to synthesis gas was studied over various Ni-based catalysts. It is shown that the mixed oxide supports CeO 2 −ZrO 2, CeO 2 −Al 2 O 3, and La 2 O 3 −Al 2 O 3, prepared using surfactant, exhibit a high catalytic activity and stability for CDRM. Temperature program reduction (TPR) results demonstrate that the presence of CeO 2, ZrO 2, or La 2 O 3 leads to the enhancement of the Ni reducibility compared to Al 2 O 3, which is an important indicator of high activity and stability of these Ni catalysts for CDRM. Our thermodynamic calculations indicate that CeO 2 could react with CH 4 to produce synthesis gas, and then CO 2 might reoxidize CeO 2− x to its oxidation state. Furthermore, CeO 2 might help in gasification of deposited carbon to inhibit the carbon formation and therefore improve catalyst stability. The presence of alumina tends not to affect the stability of the catalyst as well.