Enhancing manganese electrodeposition efficiency at high current densities utilizing a novel variable gradient chaotic current technique

Abstract

Achieving high current efficiency and minimal energy consumption in Mn electrolysis, particularly at elevated current densities while maintaining production scale, presents notable challenges. To address these, a novel chaotic current electrolysis technique with variable gradients was introduced. This approach initiates with low-density chaotic current for manganese electrodeposition, then transitions to higher currents via offset boosting. By kinetically regulating ion processes, chaotic currents are mitigated, lowering solution resistance. Variable gradients further inhibit nodule formation, enhancing current efficiency during high-density electrodeposition. Electrodeposition results indicated that chaotic current alone was ineffective in suppressing manganese nodules at 1840 A/m². However, when the current density was ≥1840 A/m², variable gradient DC exhibited a 2.83 % improvement in current efficiency over conventional DC. Additionally, variable gradient chaotic current enhanced efficiency by 5.3 %, decreased energy consumption by 0.99 k Wh/kg, and reduced solution internal resistance by 0.14Ω. Furthermore, the mechanism for reducing energy consumption has been proven to be the combined effect of Joule heating and kinetic behavior regulation. Therefore, this research can provide theoretical and technical insights, which could facilitate a large-scale, energy-efficient production of manganese in industrial settings.