Co/Al2O3 catalysts promoted with noble metals for production of hydrogen by methane steam reforming

The effect of noble metal addition on the catalytic properties of Co/Al2O3 was evaluated for the steam reforming of methane. Co/Al2O3 catalysts were prepared with addition of different noble metals (Pt, Pd, Ru and Ir 0.3 wt.%) by a wetness impregnation method and characterized by UV-vis spectroscopy, temperature programmed reduction (TPR) and temperature programmed oxidation (TPO) of the reduced catalysts. The UV-vis spectra of the samples indicate that, most likely, large amounts of the supported cobalt form Co species in which cobalt is in octahedral and tetrahedral symmetries. No peaks assigned to cobalt species from aluminate were found for the promoted and unpromoted cobalt catalysts. TPO analyses showed that the addition of the noble metals on the Co/Al2O3 catalyst leads to a more stable metallic state and less susceptible to the deactivation process during the reforming reaction. The Co/Al2O3 promoted with Pt showed higher stability and selectivity for H(2)production during the methane steam reforming. (C) 2007 Elsevier Ltd. All rights reserved.