ニッケル電解における陰極界面の液薄膜の研究 (第2報)
1960 年 76 巻 859 号 p. 27-34
詳細
1960 年 76 巻 859 号 p. 27-34
As the author described in the 1st report, it is not the composition of the bath as a whole, but that of the electrolyte arround the cathode surface that determines the quality of nickel to be electrodeposited innickel electrolysis.
The main object of the present study is to determin the optimum range for the electrolytic conditions, by obserning difference between the cathode film solution and the main bath composition.
Results obtained from the present study has more strictly clarified the conditions for good electrodeposition than studies hitherto conducter exclusively on the main bath.
Conclusions were obtained as follows:-
1. A special apparatus was made for sampling some of the electrolyte of similar composition to the cathode film, and the apparatus has been proved to work well.
2. From the results of experiment, optimum conditions that good electrodeposited nickel is obtained, are as follows. Ni++ 40g/l, H3BO3 20g/l, Na2SO4 40g/l, pH4.0-5.0, Temp. 50-55°C, C·D 120-150A/m2.
3. It is clarified that there is a close correlation between the bath composition and the electrolytic conditions. Therefor, If we wish to increase the current density, it is necessary that both the temperature and the nickel concentration are increased and the pH Value is lowered.
4. From the experiments on the cathode film, it is shown that when good nickel electrodeposition is done the characteristics is as folloms; if the x axis is to show the current density, and the y axis is to show -ΔNi++, +ΔpH, edch curve drown is Qlmost a straight line of line gradient, and there is no precipltation of Ni (OH) 2.
If the above characteristics is not seen it means a bad nickel electrodeposition.
