Electrochemical Oxidation of Molten Carbonate‐Coal Slurries

A novel approach for the electrochemical oxidation of coal is described. The electrochemical cell employed an anode of coal or carbon particles dispersed in a molten carbonate electrolyte at 500°–800°C. At these temperatures, the oxidation kinetics of coal/carbon are sufficiently rapid that high current densities can be obtained at an inert working electrode. Results presented for various forms and concentrations of carbon include open‐circuit potentials, current‐voltage curves, and product gas evolution rates. At temperatures of 700°C and above, the measured potentials were in agreement with theoretical values of the redox couple. Product gas analysis indicated that complete oxidation of carbon to was achieved, thus providing the maximum electrochemical conversion efficiency (four electrons per carbon atom). By coupling this anode with an cathode, fuel cell operation ( i.e. , electricity generation) should be feasible. The primary limitation observed in this study was the heavy chemical consumption of carbon by , which resulted in a low overall carbon conversion efficiency.