Electrochemical Reduction of Oxygen in Carbonate and Carbonate-Halide Melts.

摘要

The electrochemical reduction of O2in molten carbonates occurs through two reactions (1) 1/2O2 + CO2 + 2e = CO3(-2) and (2) 1/2O2 + 2e = O(-2). The onset of these two processes has been investigated in molten Li2CO3,the ternary eutectic (Li,Na,K)/CO3,and the two binary eutectics (LiCl,Li2CO3) and (LiF,Li2CO3). Reaction (1) was found to start at slightly negative potentials relative to the Au/O2,CO2reference electrode and depends on the supply of CO2from the melt. The onset of reaction (2) occurs at more negative polarizations;both are affected by the solubility of O2in the melt. The results are examined relative to the differing viewpoints advanced relative to the electrochemical reduction of oxygen in such molten electrolytes. (Author)