Partial Oxidation of Methane to Synthesis Gas over Alkaline Earth Metal Oxide Supported Cobalt Catalysts

摘要

The partial oxidation of methane to synthesis gas was investi- gated over the alkaline earth metal oxide supported Co catalysts. Only MgO has proved to be a suitable support. The reaction behav- ior of the MgO-supported Co catalysts was significantly influenced by the calcination temperature (T c) and Co loading. The 24 wt% Co/MgO catalyst precalcined at 800°C provided a high and stable activity; those precalcined at higher temperatures provided a lower stable activity and those precalcined at lower temperatures a lower stability. Because of the two oxidative states of Co, the structural characteristics of the Co catalysts are strongly affected by the na- lure of the support, calcination temperature, and Co loading. In the 24 wt% MgO-supported catalysts, only a solid solution of CoO and MgO was identified for T c >= 800°C, while one or two of the follow- ing compounds, CO3O4 and MgCO_2O_4, were additionally detected for T c < 800°C. Correlations among the species present in the cata- lyst, its reducibility, and its catalytic performance were established.