THE CO/CO2 AND CO ELECTRODES IN MOLTEN CARBONATES.
Abstract
The potentials of cells Au/CO,CO2/ CO3(-2)/CO2, O2/Pt and Au/CO/ CO3(-2)/CO2,O2/Pt have been determined in the ternary eutectic Li2CO3 - K2CO3 between 510 and 800C. At 800C the potential resulting from the Au/CO,CO2/ CO3(-2)/CO2,O2/Pt cell indicated that the reaction occurring at the Au electrode was CO3(-2) + CO - 2e = 2CO2. At 700C and lower, the cell potential confirmed that the reaction CO3(-2) + C - 2e = CO2 + CO dominates the high CO partial pressure range. At lower temperatures the reaction CO + 2OH(-) = CO3(-2) + H2 was observed to proceed to the right, consuming part of the incoming CO stream so that the cell potential appeared to deviate from the Nernst slope (corresponding to the reaction CO3(-2) + CO - 2e = 2CO2). The Nernst slopes and cell potentials follow the thermodynamic prediction for the electrochemical reactions occurring at the Au electrode. At low CO flow rates over the entire temperature range, and at all flow rates at higher temperatures the cell potential differed considerably from the predictions for the above reaction. The reaction CO3(-2) + 2H2 - 2e = CO + 2H2O is seen as a possible explanation for this behavior. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1969
- Accession Number
- AD0693136
Entities
People
- G. J. Janz
- P. K. Lorenz
Organizations
- Rensselaer Polytechnic Institute