Performance and durability evaluation of dry reforming in solid oxide fuel cells

The performance and durability of a single solid oxide fuel cell (SOFC) operating at 1023 K under differing reforming conditions and fed by CH4, CO2, and H2O were investigated. For dry reforming, the CO2/CH4 ratio was set to 2.7 to avoid coking in the catalyst and anode support; steam reforming was performed at H2O/CH4 = 2.5. The current-voltage characteristics of external dry reforming showed lower voltages for low fuel utilization, especially at high current densities, than those observed in steam reforming. The voltages under external dry and steam reforming were 0.880 V and 0.896 V, respectively. However, at fuel utilization values approaching 90%, the voltage under dry reforming was higher than that measured under steam reforming. External dry reforming had short term durability behavior comparable to that of external steam reforming, but the results from internal dry reforming suggested that this condition needs sensitively control regulation relative to the other characterized conditions in order not to cause coking.