Freezing-out of heavy isotopes of Kr

Autor: Cholach, A. R., Yakovin, D. V., Latkin, N. I., Sidorov, I. A.
Rok vydání: 2023
Předmět:
Druh dokumentu: Working Paper
Popis: The separation of isotopes of natural Krypton at the gas-liquid and liquid-solid phase interfaces was studied under nonequilibrium conditions using a cryogenic cell and mass spectrometry. Condensate formation during Kr cooling begins at an equilibrium temperature, which corresponds to the partial pressure of the dominant isotope 84Kr, and is accompanied by depletion of the gas phase 84Kr with a separation coefficient of ~0.92 due to the excess of the heat of condensation over the heat of dissolution by 70-100 kJ/mol. The formation of a solid phase near the freezing point is accompanied by depletion of the gas phase by heavy isotopes. The separation coefficients 86Kr, 84Kr, 83Kr, 82Kr and 80Kr are about 1.06, 1.11, 0.86, 0.86 and 0.80, respectively, after the transition of ~30% of the atoms to the solid phase. Pressure-selective condensation can be used to separate components with close boiling points when distillation and temperature-selective condensation methods are ineffective, and freezing out of heavy isotopes can be used to enrich elements with practically important isotopes.
Comment: 11 pages; 3 Figures; 3 Tables; 30 References
Databáze: arXiv