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China has become the production and consumption of zinc. Along with the zinc industry in China is developing rapidly, and how to eliminate the adverse effects of impurity ions on the deposition of zinc electrodeposited zinc impurity ions, research in this area has a lot of depth, such as the three-stage purification method can the most of the impurity ions of Co, Ni, C, Cd, As, Se) to be removed. CFC can be formed the insolubles to remove, K, NA also can be removed by jarosite iron at the same time the formation of jarosite residue removal system. Calcium and magnesium removal method of the economy, while the with the effusion cycle of power, calcium and magnesium ions in the continuous enrichment, some factories has reached 20 g / L content. Due to the increase in the concentration of magnesium ions increases the viscosity of the electrically effusion, reducing the electrical conductivity of the effusion, thereby reducing the electric current efficiency of the zinc, increasing the power consumption is a big influence on the deposition of zinc. Research in this area is relatively small. In this paper, the impurities magnesium electrodeposition of zinc and how to eliminate the adverse effects of magnesium ions on the electrodeposition of zinc did some research. The study is divided into the following four aspects: 1, measured by electrowinning experiment different magnesium ion concentration and temperature, the electrodeposited zinc current efficiency and cell voltage and power consumption. Found that at the same temperature, with the increase in the concentration of magnesium ions, zinc electrodeposition current efficiency decreases, the cell voltage and power consumption increases; in the same concentration of magnesium ions, as the temperature increases, the current efficiency the cell voltage is a downward trend, while the power consumption is increased. Came to the conclusion: of electrodeposition temperature of 35 ° C, the MG2 concentration can not exceed 15 g / L, the electrowinning temperature of 40 ° C, 45 ° C, the the MG2 concentration must not exceed 10 g/L-15g/L, otherwise electrowinning will not function properly carried out. 2, the determination of the type of the magnesium ion concentration and temperature, the electrically the effusion basic nature: density, viscosity, conductivity. Found that: at the same temperature, with the increase in the concentration of magnesium ions, electrically fluid density and viscosity increases, the conductivity increased and decreased with the concentration of magnesium ions; in the same magnesium ion concentration, electrical effusion with the temperature increased, the density and viscosity of the solution was a downward trend, reduced at high temperatures, to a large extent, increases while the electrical conductivity effusion. 3, by studying a single additive impact on the the magnesium zinc sulfate electric effusion, filter out the the electrowinning effect better additives, and then a certain ratio synthetic compound additives. Synthesized a composite additive A2 have some effect on magnesium sulfate, zinc electrowinning zinc, determine the A2 optimum addition level of 15 mg / L. Finally, add the A2 and A2 does not add to the precipitation of the zinc surface microscopic analysis. 4, the use of electrochemical workstation polarization curves, Tafel curves, cyclic voltammetry curves to study the mechanism of magnesium ions on the electrodeposition of zinc. The results show that with the increase in the concentration of magnesium ions, the electric current density of the effusion decreased, identified by the zinc deposition reaction mechanism inferred magnesium ion impact mechanism for the electrodeposition of zinc.
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