Industrial & Engineering Chemistry Research, Vol.56, No.21, 6136-6144, 2017
Competition of Oxygen Evolution and Desulfurization for Bauxite Electrolysis
To understand the relationship between oxygen evolution and desulfurization for bauxite electrolysis, the apparent activation energy of the anode reaction was examined by analyzing the polarization curves. The results showed that the apparent activation energy of the anode reaction for bauxite electrolysis with a low slurry concentration was lower than that of water electrolysis, indicating that the bauxite particles had some microcell disturbance effects on liquid diffusion. As expected, it was also lower than that of bauxite electrolysis with a high slurry concentration, indicating that the bauxite particles had some inhibition effects on oxygen evolution. Compared with adding bauxite, the increase in stirring speed did not change the concentration polarization of water electrolysis, indicating that the microcell disturbance effect of the bauxite particles was more important. Compared with the low slurry concentration electrolysis, the high slurry concentration electrolysis resulted in a low desulfurization ratio and high current efficiency during bauxite electrolysis.