Gas Atmosphere Effects Over the Anode Compartment of a Tubular Direct Carbon Fuel Cell Module

This study examines the performance of a tubular direct carbon fuel cell (DCFC) with varying gas atmosphere. DCFC performance is higher under a CO2 atmosphere when compared with a N2 atmosphere, where mass transport limitations in the anode compartment and the additional two-electron oxidation pathway from CO contribute. This hypothesis is verified by comparing the slurry arrangement to a solid working anode where mass transport is not required. In order to maximize the carbon utilization efficiency, operating below the thermodynamic temperature limit for reverse Boudouard gasification (700 °C) is recommended with agitation in slurry-based systems. For a maximum power output, operating under CO2 at higher temperatures (>800 °C) and passing the CO containing flue gas over an oxygen reduction cathode achieve optimal results.