Catalytic production of hydrogen from methanol

Catalytic production of hydrogen by steam reforming of methanol is an attractive option for use in decentralised production of clean electrical energy from fuel cells. Methanol fuelled solid polymer fuel cell (SPFC) systems are promising candidates for stationary and mobile applications such as passenger cars. Present methanol reformers are usually of the packed bed type which suffer from problems such as the occurrence of hot and cold spots and the slow response at start-up and during transients. These disadvantages are due to the slow heat transfer in the packed bed. Metal-supported catalyst systems that integrate the endothermic methanol steam reforming with the exothermic combustion of methanol or hydrogen containing gas from the fuel cell offer good heat transfer characteristics which are beneficial for the dynamical response at start-up and during transients, For methanol steam reforming, the concept of a washcoated heat exchanger showed better performance as compared to washcoated foam and packed beds. This is attributed to the good heat transfer characteristics of the heat exchanger. More than 600 l/h of hydrogen can be generated at methanol conversions higher than 95%. By proper temperature control, 450 h of continuous operation has been achieved with a washcoated reactor at an average methanol conversion >90%. (C) 2000 Published by Elsevier Science B.V.