Fuel cells are one of the most attractive distributed power generation technologies. They combine hydrogen and oxygen to produce electricity, with water and heat as the by-products. Since the conversion of the fuels to energy takes place directly without combustion, the process is highly efficient, clean, and quiet. However, problems associated with hydrogen sources and storage, and limitations in fuel flexibility are delaying the commercialization of fuel cells as a competitive technology for both transportation and stationary applications.
Researchers at CEER are working on the development of a new technology that can help confront all the issues mentioned above. The technology is called “Ammonia Electrolysis” and the electrochemical cell is called “Ammonia Electrolytic Cell (AEC).
The AEC operates as follows: aqueous ammonia (NH3/H2O) in the presence of potassium hydroxide (KOH) is fed into the anode compartment of the AEC where NH3 is oxidized in the presence of OH- according to
2NH3 + 6OH- -------> N2 + 6H2O + 6e-
At the cathode a solution of KOH is supplied and water is reduced in alkaline medium according to
2H2O + 2e- -------> H2 + 6OH-
Therefore the overall reaction is given by
2NH3 -------> N2 + 3H2
The theoretical voltage for the production of hydrogen at 25°C through electrolysis of ammonia in alkaline media is 0.058 V with an energy consumption of 1.55 W-h per gram of H2 produced. KOH is the electrolyte for the system and water acts as the solvent, that is, neither KOH nor water are consumables during the operation of the cell.