SIMULTANEOUS STEAM AND CO2 REFORMING OF METHANE TO SYNGAS OVER NIO MGO/SA-5205 IN PRESENCE AND ABSENCE OF OXYGEN/

Steam reforming, CO2 reforming and simultaneous steam and CO2 reformin g reactions of methane for its conversion into syngas (H-2 and CO) ove r NiO/MgO/SA-5205 catalyst (prepared by depositing NiO on MgO precoate d SA-5205 support) have been investigated at different process conditi ons. In some cases O-2 was present in the feed, while in other cases i t was not. The catalyst has been characterised by its temperature prog rammed reduction and also, after its reduction, by temperature program med desorption of hydrogen. It showed high activity and selectivity in the above methane-to-syngas conversion reactions at low contact times . The H-2/CO product ratio in the simultaneous methane conversion reac tions showed a strong dependence on the feed composition; such depende nce is increased by increasing the concentration of steam relative to that of O-2 and/or CO2 in the feed. In the oxy-steam and/or CO2 reform ing reactions, there is a direct coupling of the exothermic and endoth ermic reactions and hence these processes over the catalyst occur in t he most energy efficient and safe manners, requiring little or no exte rnal energy. The net heat of reactions in these processes is strongly influenced by the reaction temperature and/or CH4/O-2 ratio in the fee d. In the simultaneous steam and CO2 reforming of methane in both the presence and absence of O-2, it is possible to convert methane into sy ngas with high conversion (above 97%) and 100% selectivity for both CO and H-2. (C) 1998 Elsevier Science B.V.