| Zinc oxide raw materials and zinc oxide ores, containing high fluorine, chloride and iron, can 't be treated to produces electrowinned zinc by routine process. High-purity zinc using in non-mercury zinc powders is prepared only by using vacuum distillation or rectify process from zinc of the zero grade. In this article treating complex zinc oxide materials and preparing high-purity zinc are the primary objects of this study. A new process of preparing high-purity zinc directly from complex zinc oxide materials or zinc calcine was invented. The contents IN this study include thermodynamic calculating, plotting potential-pH figures of purification process, determinhig electrochemical kinetics of cathode reactions and anode reactions, effecting of additives on morphology and crystallographic orientations of electrowinned zinc hi the system of Zn(n)-NH3-NH4Cl-H2O, successfully applying basic theory to treating zinc calcine and zinc fume dusts from slags of smelting lead.According to the principles of simultaneous equilibrium and aqueous electronic charge neutrality, the thermodynamic data in the system of Zn(n)-NH3-NH4Cl-H2O have been calculated and the solubility figures of ZnO in the system have been plotted. The solubility regular and high solubility area of zinc oxide were discovered and this system has higher zinc solubility than ammoniacal ammonium sulfate system and ammoniacal ammonium carbonate system at same concentration. When ratio of ammonia concentration to ammonium chloride concentration is lower than 1, equilibrium solubility of zinc is almost proportionate to ammonia concentration. But when the ratio is larger than 1, the solubility almost not increases. When ammonium chloride concentration is constant, the dominated species of zinc are changed from ZnCli2-1 to Zn(NH3)42+ with the increasing of ammonia concentration. The absolute average error between experimental values and theoretically calculated values of zinc equilibrium concentration is 11.37% in ammoniacal ammonium chloride solution.According to the thermodynamic calculation and the critical stability constants of impurities, relationships between potential and pH values have been calculated out and potential-pH figures have been plotted in the system of Men+-NH3-NH4Cl-H2O. When Men+ concentration (Men+ representing Cu2+, Cu+, Pb2+, Ni2+, Cd2+, Co2+) is lOmol/L, the subtractive values between EMe|Me+ (Men+ representing Cu2+, Pb2+, Ni2+,Co2+) and E are higher than 0.3 volt. So impurities of Cu2+, Pb2+,Ni2+, Co2 can be cemented completely. The value between u+/Cuand E , is small, so Cu must be oxidized to Cu2+ before cemented. Thedifference ofEZn2+/ZnandEC(1/cd ,Co2/Co is small, cemented cadmiumand cobalt aren't resolved at room temperature in the system of Zn(n)-NH3-NH4Cl -H2O but they are resolved at high temperature in system of ZnSO4-H2O.Anodic reactions of electrowinning zinc, producing nitrogen, were analyzed theoretically and confirmed by experiments in the system of Zn (n)-NH3-NH4Cl-H2O. Electrochemical kinetics of cathode reactions and anode reactions were studied by using potentiostate. The electrochemical kinetics equation of anodic reactions was determined as follow.K = 3.066 x 105 x F[Cr ]1056 exp(--^i)RTThe electrochemical kinetics equation of cathodal reactions was determined as follow.RTThe effects of various additives alone or multiply on cathodal linear polarization and cyclic voltammogram were investigated by using methods of scanning potentiostate and cyclic voltammeter. Cyclic voltammograms has been measured at stirring. We can conclude that glue stone absorbed on the cathodal surface affects on preventing cathodal electrochemistry reactions, not on the transfer velocity of zinc ions. We can conclude that T-B affects on preventing the transfer velocity of zinc ions for it is a strong cation and transfers with zinc-ammonia complexes. Zinc-T-C complex is easier to form than zinc-ammonia complex, which can largely increase transfer velocity.The effects of zinc concentration, electrode space, current d...
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