Design of stable Ni catalysts for partial oxidation of methane to synthesis gas

The supported Ni catalysts with CaAl2O4 spinel compound layer existed between Ni and Al2O3 have been prepared, and the effect of the CaAl2O4 spinel layer on the stability of the catalysts for the partial oxidation of methane to syngas (CO + H-2) has been investigated at high space velocity (250 L . g(-1) . h(-1)). Also, the catalysts have been characterized by XRD, TG/DTA. The Ni catalysts with CaAl2O4 spinel layer existed between Ni and Al2O3 show good stability for this process with the CH4 conversion of similar to 83%, syngas selectivity of >90% and the coke deposit of <1 wt% during a longtime running at 873 K. The CaAl2O4 spinel layer can effectively suppress the phase transformation to form NiAl2O4 spinel phases and stabilize the Ni tiny crystallite, to which the good stability of the catalyst contributes. (C) 1998 Academic Press.