A time-resolved in situ quick-XAS investigation of thermal activation of Fischer-Tropsch silica-supported cobalt catalysts

摘要

Quick X-ray absorption spectroscopy (XAS) provides quantitative information about the composition of supported metal phases during catalyst activation. Decomposition of SiO _2-supported cobalt nitrate in diluted NO leads to the rapid formation of cobalt(II) hydroxynitrates below 100 °C. Their decomposition starts progressively between 110 and 170 °C to give cobalt oxide nuclei, which contribute to the enhancement of the metal oxide dispersion (see figure).