Diffusible ions, recycling

The schematic of CO2 capture in a conventional MCFC is shown in Figure 15.31. Thus, C02-laden flue gas from a coal-fired power plant is used directly as the oxidant on the cathode of an MCFC. The CO2 acts as a vehicle molecule (Figure 15.2) for the elementary anion 0 , forming the carbonate ion, which diffuses across the supported molten-carbonate electrolyte layer. It unloads its payload at the anode, where the fuel is oxidized into H2O and more CO2. Instead of recovering and recycling the CO2 from the anode back to the cathode to ferry more ions as in conventional MCFC, in the proposed schematic shown in Figure 15.31, the CO2 from the anode is recovered and sequestered. 

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