Hydrogen evolution and dissolution on graphite electrodes in molten potassium bisulphate : II. Kinetics and mechanism of the reactions on porous graphite
The electrochemical evolution and dissolution of hydrogen in potassium bisulphate melt have been studied on porous graphite electrodes in the temperature range from 245–280°C. Kinetic parameters were obtained in the conventional way both for steady as well as non-steady conditions and are compared t...
| Authors: | , , |
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| Format: | article |
| Status: | Published version |
| Publication Date: | 1972 |
| Country: | Argentina |
| Institution: | Universidad Nacional de La Plata |
| Repository: | SEDICI (UNLP) |
| Language: | English |
| OAI Identifier: | oai:sedici.unlp.edu.ar:10915/121132 |
| Online Access: | http://sedici.unlp.edu.ar/handle/10915/121132 |
| Access Level: | Open access |
| Keyword: | Ciencias Exactas Química Hydrogen Electrochemical evolution Kinetic parameters |
| Summary: | The electrochemical evolution and dissolution of hydrogen in potassium bisulphate melt have been studied on porous graphite electrodes in the temperature range from 245–280°C. Kinetic parameters were obtained in the conventional way both for steady as well as non-steady conditions and are compared to those previously derived for dense graphite electrodes. The cathodic and anodic reactions are not straightforwardly complementary processes. The former is explained in terms of a conventional reaction mechanism for the hydrogen electrode involving either a hydrogen adatom combination reaction or a hydrogen ion plus adatom reaction as rate-determining. The anodic reaction is interpreted in terms of various possible mechanisms comprising a one-half order rate equation with respect to the hydrogen gas pressure. The most likely mechanism comprises a competition between the ionization of hydrogen adatoms and the oxidation of graphite at active sites located at the surface. Thermal effects are in agreement with the postulated reaction mechanisms. |
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