Kinetics of the pyrolysis of beryllium hydride
| Autor: | W.G. Nigh, G.R. Schneider |
|---|---|
| Rok vydání: | 1970 |
| Předmět: |
Hydride
General Chemical Engineering Inorganic chemistry Nucleation Analytical chemistry General Physics and Astronomy Energy Engineering and Power Technology chemistry.chemical_element General Chemistry Activation energy Rate equation Atmospheric temperature range Beryllium hydride chemistry.chemical_compound Fuel Technology chemistry Beryllium Pyrolysis |
| Zdroj: | Combustion and Flame. 15:223-231 |
| ISSN: | 0010-2180 |
| DOI: | 10.1016/0010-2180(70)90002-7 |
| Popis: | The kinetics of the pyrolytic decompositions of beryllium hydride, BeH 2 has been studied over the temperature range 205–250°C. When the fraction decomposed is planted time the reaction exhibits a sigmond-shaped curve on the processes. The initial portion of the phase (has been correlated with power law which is the result of using a model assuming random formation of beryllium and a linear growth rate of the nuclei. The data indicate that the exponent on in the power law was 7 for 95.6% hydride and about 5 for 93.1% hydride. A contracting-volume model has been to describe the final portion of the acceleratory phase and the deceleratory phase (0.35 0.80. Values of the activation energy were found to be between 23 and 27 kcal mole for the 95.6% hydride and between 23 and 30 kcal mole for the 93.1% hydride for all of the models used. Any rate equation having the general form will produce similar activation energies. The hydride pyrolysis rate was unaffected by beryllium metal addition, by washing in -hexane, ether, and benzene, or by exposure to mercury vapor. X-ray irradiation changed the pyrolysis rate in a way that was consistent with the production of more nucleation sites. Grinding the hydride also increased the decomposition rate but lowered the exponent on in the power law from 7 to about 5. |
| Databáze: | OpenAIRE |
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