1990 Fiscal Year Final Research Report Summary
Analysis on the Wetting Behavior of Mercury to Zinc in a KOH Solution.
| Project/Area Number |
01550524
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
金属精錬・金属化学
|
|---|
| Research Institution | Kyushu Institute of Technology |
|---|
Principal Investigator |
NAKAMURA Takashi Kyushu Institute of Technology, Department of Materials Science & Engineering, Associate Professor, 工学部, 助教授 (20112360)
|
|---|
| Project Period (FY) |
1989 – 1990
|
| Keywords | Alkaline battery / Anodic materials / Zinc / Mercury / Interfacial tension / Wetting |
|---|
| Research Abstract |
Anodic dissolution tests of zinc in KOH solutions were carried out. Dissolution rates became faster in order of (0001) single crystal plane, poly-crystaline plane and (1100) single crystal plane. It was suggested that dissolution rates depended on the atomic density of the plane. Very small amount of Hg took a big role to prevent the self-dissolution of zinc in a KOH solution if zinc was coated with Hg thinly and uniformly. Therefore, a processing of thin and uniform coating of Hg on zinc anodes was a key point to reduce Hg in alkaline batteries.
Wetting of Hg on zinc in a KOH solution was evaluated using spreading coefficient (S=gamma KOH/Zn - (gamma Hg/Zn + gamma KOH/Hg)). Surface tensions of KOH solutions and interfacial tensions between Hg and KOH solutions were measured to calculate the values of S. The values of S in a KOH-Zn-Hg system were always positive and increased with an increase of KOH concentration in the system. This result indicated that a coating of Hg on zinc powder should be done in a high KOH concentration solution to achieve a thin and uniform coating of Hg.
|
