Evaluation of Activities of Carbons in Chemical Equilibrium with Uranium Carbonitride
| Autor: | Masahiro Katsura, Masanobu Miyake, Kazuo Hamada, Masayuki Hirota |
|---|---|
| Rok vydání: | 1992 |
| Předmět: | |
| Zdroj: | TANSO. 1992:84-90 |
| ISSN: | 1884-5495 0371-5345 |
| DOI: | 10.7209/tanso.1992.84 |
| Popis: | A mixture of uranium sesquinitride and carbon was prepared by the reaction of UC or UC2 with N2 in the temperature range from 700 to 1400°C. When the mixture of uranium sesquinitride and carbon is kept at temperatures above 1200°C in the atmosphere of N2 at low pressure, the state where uranium carbonitride (UC1-x, Nx) and carbon are present together in chemical equilibrium will be established. A thermodynamic analysis suggests that, in the equilibrium state, the composition of UC1-xNx is determined by the chemical activity of carbon, ac, which is related to the chemical potential of the carbon, μE c, by the equation, μc=μc°+RT 1n ac. Here μc° refers to graphite, which is usually taken as the standard state of carbon (ac=1). Mixtures of U2N3 and carbon with several degrees of graphitization were heat-treated at 1400°C, and the composition of UC1-xNx in the reaction product was determined. From these experimental results and the thermodynamic analysis, values of the activity of the carbon coexisting with UC1-xNx were estimated. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|