1992 Fiscal Year Final Research Report Summary
DEVELOPMENT OF CONTINUOUS ZINC ELECTROWINNING
| Project/Area Number |
02555168
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| Research Category |
Grant-in-Aid for Developmental Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
工業物理化学・複合材料
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| Research Institution | YAMANASHI UNIVERSITY |
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Principal Investigator |
FURUYA Nagakazu YAMANASHI UNIV., 工学部, 教授 (70020485)
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| Co-Investigator(Kenkyū-buntansha) |
SHIBATA Masami YAMANASHI UNIV., 工学部, 助教授 (40115316)
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| Project Period (FY) |
1990 – 1992
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| Keywords | Gas-diffusion Electrode / Hydrogen Nonode / Zinc / Electrowinning |
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| Research Abstract |
Electrowinning is the most important method by which zinc is produced. This process uses a low current density (57mA/cm^2) and high cell voltage (3.6V), because the anode polarization and the ohmic drop in the electrolyte are large. The anode is made from a lead-silver alloy which usually contains 0.5% Ag. The cathode is Al plate.
We replaced the anode to a gas diffusion electrode (400cm^2) and hydrogen is fed to the gas diffusion electrode and the cathode to 1mphi Al rotating disk. The gap between anode and cathode is 4mm. The electrolyte solution, containing 60g/1 Zn and 180g/1 H_2SO_4 was purified by Zn powder. The new type continuous zinc electrowinning system produced a belted zinc. The cell voltage is 1.81V at 0.35A/cm^2 and 2.67V at 0.7A/cm^2 respectively. The current efficiency 90% at 0.45A/cm^2 and 86.5% at 0.7A/cm^2 respectively. The zinc purity is 99.999%. The energy usage of the system is 1400kWh and 380m^3 H_2 gas per ton of zinc. This system will be easily put into practice.
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