FUNDAMENTAL RESEARCH OF PHYSICAL AND ELECTROCHEMICAL PROPERTIES OF ELECTROLYTES IN INDUSTRIAL PROCESS.

工业过程中电解质的物理和电化学性质的基础研究。

• 批准号: 05650732
• 负责人: FUKUSHIMA Hisaaki
• 金额: $ 1.41万
• 依托单位: Kyushu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05650732/
• 关键词: Industrial electrolysis; Zinc; Silver; Electric conductivity; Density; Viscosity; Energy efficiency; Productivity; 銅

The selection of the instruments for the measurements of the physical properties such as electric conductivity, density and viscosity of electrolytes was made on a basis of their price and measurement accuracy. Using these instruments, the physical properties of industrial Zn electrowinning and Zn electroplating baths employed for the surface finishing of steel sheets for automobile body were measured to compare the properties between both electrolytes. As a result, the conductivity of the electrowinning bath is extremely higher than that of electroplating bath, while density and viscosity of electroplating bath show the higer values than the electrowinning bath. This indicates that the composition of electrowinning bath is determined from the viewpoint of high energy efficiency. In the Zn electroplating of steel sheets, since the applied current density is increased by the enhancement of the limiting current density due to vigorous agitation and high concentration of Zn ion in bath, the main emphasis is placed on the productivity of Zn plating.These physical properties were also measured in electrorefining and electroplating baths of Ag. The conductivity of electrorefining bath(nitrate type)is not so high because of a small amount of free nitric acid in bath. This indicates that re-dissolution of the deposited Ag can occur in the bath having high concentration of nitric acid. In the electroplating of Ag from cyanide bath, the discharge of Ag ion from cyanide complex takes place a significant cathodic overvoltage to improve the surface appearance of deposited Ag.Finally, the physical properties of the electrolytes were compared between the synthesized and industrial sulfate baths of Zn. The small differences in their values are observed between both electrolytes because of the presence in various metallic ions and organic additives in industrial bath.

电解质的电导率、密度和粘度等物理性质的测量仪器的选择是根据其价格和测量精度进行的。利用这些仪器，对工业电积锌和汽车车身钢板表面精整用电镀锌液的物理性能进行了测试，比较了两种电解液的性能。结果表明，电积液的电导率远高于电镀液，而电镀液的密度和粘度均高于电积液。这表明电解液的组成是从高能量效率的观点来确定的。在钢板电镀锌中，由于剧烈搅拌和镀液中锌离子浓度高，极限电流密度增大，从而提高了施加的电流密度，因此重点放在镀锌的生产率上，并在电解精炼和电镀银的镀液中测定了这些物理性能。硝酸盐型电解精炼槽的电导率不高，是因为电解液中游离硝酸含量少。这表明在具有高浓度硝酸的浴中可以发生沉积的Ag的再溶解。在氰化物电镀银过程中，氰化物络合物中Ag离子的放电产生了显著的阴极过电压，改善了银镀层的表面形貌。最后，对合成的硫酸盐锌镀液与工业硫酸盐锌镀液的物理性能进行了比较。由于在工业浴中存在各种金属离子和有机添加剂，在两种电解质之间观察到它们的值的微小差异。