The Study Of The Anode Kinetics During The Electrolytic Manganese Process

Currently, the further increase of electrolytic manganese efficiency has reached abottleneck. So it is necessary to expand the horizons and conduct a comprehensivestudy of all aspects for energy-saving operating in electrolytic manganese. The new en-ergy-saving way should be seek under the theoretical basis of strict modern physics andchemistry (Chemical Physics).Electrolytic manganese anode process involves two major competitive reactions,precipitation of oxygen and production of the anode mud, which contains a complex ofelementary steps, and the nature of the coupling between each primitive has not yetformed a unified understanding. Therefore, a profound understanding on the dynamicmechanism of anodic process has been an important prerequisite in order to improvecurrent efficiency, reduce energy consumption and the production of anode mud. Thispaper will analyze the potential oscillation of the anodic process to study the influencebetween external control parameter conditions and oscillation phenomenon. The dy-namic mechanism of the anodic process was also explored, and an effective way to finda new method of electrolytic manganese energy-saving and emission-reduction was alsoprovide.The contents and conclusion of the experiment were shown as followed:1. Electric potential and current oscillations both do coexist in the electrochemicaloscillation which was confirmed by the cyclic voltammeter experiment. Layer of porousmanganese oxide thin films which grow on the anode plate was confirmed as the reasonfor the including of potential oscillation phenomenon by scanning electron microscopy(SEM) analysis. Intermittent electrochemical experiments were carried out and the re-sults shown that anode process was divided into two cycles. One was potential oscilla-tion cycle which was induced by membrane structure and the other was the growth,rupture and re-growth cycle of membrane structure. The anodic process contained asfollow: The growth of layered porous membrane oxide thin films, the induction of elec-tric potential oscillation, the potential oscillations layered porous film of oxide filmrupture, potential oscillation, the re-growth of the oxide film of the layered porousmembrane and again evoked potential oscillations.2. The effect of current density on potential oscillation was studied. The resultsshowed that the maximum value of potential oscillations appeared as286.3mV. Then it will decrease slowly, and frequency increase. At this time, the system was evolved as“near-equilibrium linear region-periodic oscillation Regional-chaotic oscillationArea” system. The effect on potential shocks by the concentration of manganese ionwas also studied. The results showed that the increase of amplitude and frequency pre-sented linear characteristic when the concentrations of manganese ion was low (lessthan5g/L). While in high concentrations (greater than5g/L) region, amplitude andfrequency appears tiny fluctuations near225mV and0.09Hz respectively. The systemevolved as “near-equilibrium linear region-periodic oscillation region” system. Theimpact on the power consumption by potential oscillations was investigated. The resultsshowed that the electric potential oscillation phenomenon contains a power-adjustableregion, which will lead to the relative reduction in power consumption up to10.91%.With the further controlling of voltage oscillation, a new electrolytic energy consump-tion "saddle point" may be found in the orderly oscillation area.3. According to the phenomena of electrolytic manganese anode experiment, onepossible reaction mechanism of electrolytic manganese anode was presented combinedwith the literature reports. The dual dynamic model for the anodic reaction system wasestablished. The linear stability analysis was carried out on the model with the MAT-LAB software employed and the oscillation phenomena were simulated with the appro-priate parameters. Both the simulation and the experiment were shown the same oscilla-tion frequencies.