Desulfurization from Bauxite Water Slurry (BWS) Electrolysis

Competition of Oxygen Evolution and Desulfurization for Bauxite Electrolysis

“…The current efficiency of desulfurization was calculated by eq . Compared with the current efficiency for desulfurization from bauxite electrolysis with 25 g/L slurry, bauxite electrolysis with 100 g/L slurry was more conducive to desulfurization, being in agreement with the effects of the slurry concentration on desulfurization in NaCl solution . From Figure , the higher the slurry concentration, the higher the required activation energy of O 2 produced from water, indicating that O 2 was more difficult to form, and thus, the oxidation efficiency was higher due to the amount of • OH.…”

“…Therefore, the efficiency of • OH used (at high potential) was improved at a high slurry concentration. From our previous results, the desulfurization ratio decreased with increasing slurry concentration, but the current efficiency increased with the slurry concentration. The result was in accord with our previous results, and verified the nature of the increase in the current efficiency.…”

“…Therefore, the increase in current efficiency was mainly a result of the increase in reactions and . We considered that the direct oxidation (reaction ) contributed to the increase in current efficiency, because the slurry concentration was changed only under the same conditions (entering the same electric quantity) …”

“…Electrolysis desulfurization is advantageous as it requires mild operation conditions and can potentially achieve high desulfurization ratio levels. , More importantly, the electrolysis process could simultaneously remove organic and inorganic sulfurs in minerals (e.g., coal electrolysis). Furthermore, on the basis of our previous studies, , the electrolysis desulfurization was indeed more suitable to inorganic ores than organic ones (e.g., coal electrolysis) , that would form some organic product cover on the anode and thus deactivate the reaction during the electrolysis.…”

“…The previous research has shown that the slurry concentration, pH, E h , NaOH concentration, and stirring rate are all important parameters in the desulfurization. The electrolysis process has been examined by using desulfurization with conditions.…”