Simultaneous oxidative conversion and CO2 or steam reforming of methane to syngas over CoO–NiO–MgO catalyst

Abstract

CO2 reforming, oxidative conversion and simultaneous oxidative conversion and CO2 or steam reforming of methane to syngas (CO and H2) over NiO–CoO–MgO (Co: Ni: Mg=0·5: 0·5:1·0) solid solution at 700–850°C and high space velocity (5·1×105 cm3 g−1 h−1 for oxidative conversion and 4·5×104 cm3 g−1 h−1 for oxy-steam or oxy-CO2 reforming) for different CH4/O2 (1·8–8·0) and CH4/CO2 or H2O (1·5–8·4) ratios have been thoroughly investigated. Because of the replacement of 50 mol% of the NiO by CoO in NiO–MgO (Ni/Mg=1·0), the performance of the catalyst in the methane to syngas conversion process is improved; the carbon formation on the catalyst is drastically reduced. The CoO–NiO–MgO catalyst shows high methane conversion activity (methane conversion >80%) and high selectivity for both CO and H2 in the oxy-CO2 reforming and oxy-steam reforming processes at ⩾800°C. The oxy-steam or CO2 reforming process involves the coupling of the exothermic oxidative conversion and endothermic CO2 or steam reforming reactions, making these processes highly energy efficient and also safe to operate. These processes can be made thermoneutral or mildly exothermic or mildly endothermic by manipulating the process conditions (viz. temperature and/or CH4/O2 ratio in the feed). © 1998 Society of Chemistry Industry