Electrosynthesis of Ferrate (VI) ion Using High Purity Iron Electrodes: Optimization of Influencing Parameters on the Process and Investigating Its Stability

摘要

This study is focused on the determination of optimum conditions for ferrate (VI) production and itsstability. The effect of various operating parameters, such as NaOH concentration, current density,temperature and electrolysis duration on the yield of electrochemical ferrate (VI) ion production wasinvestigated for high purity iron electrodes. Cyclic Voltammetry (CV) studies were carried out tocharacterize a process that takes place on the working iron electrode. The surface of high purity ironelectrode was analyzed by Scanning Electron Microscopy (SEM). Electrosynthesized ferrate (VI) ionstability at different conditions was also investigated. Factors influencing the stability were initialferrate (VI) ion concentration, alkalinity, temperature, and pH of the solution. Ferrate (VI) ion showedhigh stability at higher alkalinity, lower temperatures, increasing ferrate (VI) ion concentration and pHin the range between 9.2 and 10. Current efficiency and energy consumption were used for theoptimum parameters determination for the ferrate (VI) production. According to the experiments, the2 optimum conditions were NaOH (as anolyte) concentration of 20 M, current density of 1.47 mA/cm ,o and temperature of 30 1 C with electrolysis duration of 1.5 hours. Ferrate (VI) ion solutions withcontents up to 2.0 mM were produced in the electrochemical cell.