DCFC with Molten Carbonate Electrolyte

The DCFC with molten carbonate electrolytes are the most commercial type of fuel cells. Molten carbonate as an electrolyte has a number of advantages such as high ionic conductivity long-term stability of CO2 and catalysis of carbon oxidation. These DCFCs work at high operating temperatures of 600-850°C. Usually, mixed molten 

In this cell, 68% K2CO3 and 32% Li2C03 was used as electrolyte. The cathode is made of sintered frit composed of fine nickel particles, whereas the anode consists of paste of carbon particles ( 100 pm). The electrode reactions are given as  

Hence 2 carbon dioxide needs to be recycled from the anode to the cathode department. It must be noted that the electrode assembly consists of a separator made 

4 DCFC with Oxide Ion Conducting Soiid Electrolyte 

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Nabae Y and Pointon K D (2008), Electrochemical oxidation of solid carbon in hybrid DCFC with solid oxide and molten carbonate binary electrolyte . Energy Env Sci, 1,148-155. 

Direct Carbon Fuel Cells (DCFC). In direct carbon fuel cells, solid carbon (presumably a fuel derived from coal, pet-coke or biomass) is used directly in the anode, without an intermediate gasification step. Concepts with solid oxide, molten carbonate, and alkaline electrolytes are all under development. The thermodynamics of the reactions in a DCFC allow very high efficiency conversion. Therefore, if the technology can be developed into practical systems, it could ultimately have a significant impact on coal-based power generation. 

Molten KOH or NaOH is used as the electrolyte, which is contained within a metallic container. The metallic container acts as the cathode and a carbon rod dipped into electrolyte acts as both fuel and anode of the cell. Molten hydroxide electrolytes possess advantageous features such as high ionic conductivity, low overpotential and high carbon oxidation rate with a low operation temperature of 600°C for DCFC, which make its components fabrication economical. The dominant reaction product would be CO2 instead of CO. The ceU reactions are given as follows ... 

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