The effects of ultrasound on the direct electrosynthesis of solid K2FeO4 and the anodic behaviors of Fe in 14 M KOH solution

The effects of ultrasound on the direct electrosynthesis of solid K₂FeO₄ and the anodic behaviors of pure iron were investigated, and the physical properties of samples were characterized by means of X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. The experimental results showed that the existence of ultrasound can decrease the formation potential of ferrate(VI) and the passivation extent of iron anode, and this leads to higher current efficiency for the direct electrosynthesis of solid ferrate(VI) at 65 °C in 14 M KOH solution. It was also found that, in the experimental scope suitable ultrasonic power (14.6 W), shorter electrolysis duration and smaller electrolysis current can improve the apparent current efficiency of the electrosynthesis, and the largest current efficiency under suitable experimental conditions reached 77.2%.