Vapor pressure isotope effect in /sup 13/CClF/sub 3///sup 12/CClF/sub 3/ by cryogenic distillation kinetics

Vapor pressure isotope effect in /sup 13/CClF/sub 3///sup 12/CClF/sub 3/ by cryogenic distillation kinetics [electronic resource]

The vapor pressure of /sup 13/CClF/sub 3/ relative to the vapor pressure of /sup 12/CClF/sub 3/ was measured as a function of temperature between 169/sup 0/ and 206/sup 0/K by using a modified Bigeleisen distillation column. The transient build-up of the isotopic concentration gradient along the len...

Full description

Saved in:
Bibliographic Details
Online Access: Online Access
Main Authors: Ishida, T. (Author), Wieck, H. J. (Author)
Other Authors: Brooklyn Coll., N.Y. (USA) (Researcher)
Format: Government Document Electronic eBook
Language:English
Published: Washington, D.C : Oak Ridge, Tenn. : United States. Energy Research and Development Administration ; distributed by the Office of Scientific and Technical Information, U.S. Department of Energy, 1975.
Subjects:
Carbon 13.
Isotope Effects.
Alkanes.
Carbon 12.
Carbon Dioxide.
Cryogenics.
Diagrams.
Distillation.
Equations.
Gas Chromatography.
Gases.
Low Temperature.
Mass Spectroscopy.
Organic Chlorine Compounds.
Organic Fluorine Compounds.
Oxidation.
Tables.
Vapor Pressure.
Very High Temperature.
Carbon Compounds.
Carbon Isotopes.
Carbon Oxides.
Chalcogenides.
Chemical Reactions.
Chromatography.
Even-Even Nuclei.
Even-Odd Nuclei.
Fluids.
Hydrocarbons.
Information.
Isotopes.
Light Nuclei.
Nuclei.
Organic Compounds.
Organic Halogen Compounds.
Oxides.
Oxygen Compounds.
Physical Properties.
Separation Processes.
Spectroscopy.
Stable Isotopes.
Thermodynamic Properties.
Inorganic, Organic, Physical And Analytical Chemistry.
Description
Summary:The vapor pressure of /sup 13/CClF/sub 3/ relative to the vapor pressure of /sup 12/CClF/sub 3/ was measured as a function of temperature between 169/sup 0/ and 206/sup 0/K by using a modified Bigeleisen distillation column. The transient build-up of the isotopic concentration gradient along the length of the packed column during the start-up period was monitored by taking samples from the condenser section as a function of time. The gaseous samples were completely oxidized to carbon dioxide in the presence of a platinum catalyst and a large excess of oxygen at temperatures between 1050 and 1100/sup 0/C. The combustion products were purified by means of gas chromatography, and the purified carbon dioxide samples were analyzed in a Nier-type isotope-ratio mass spectrometer. The data of each distillation run were reduced in the light of Cohen's theory of the kinetics of square cascade of close-separation stages. The vapor pressure isotope effect for the carbon substitution in CClF/sub 3/ at temperatures between 169/sup 0/ and 206/sup 0/K was found to be an inverse effect and to be rather insensitive to changes in temperature. The relative vapor pressure may be expressed 1n(P'/P) = ((1.5 +- 14.1)/T/sup 2/) - ((0.159 +- 0.076)/T), or 1n(P'/P) = ((0.173 +- 0.098)/T) - ((0.11 +- 0.53) x 10/sup -3/), where P' and P are the vapor pressures of /sup 12/CClF/sub 3/ and /sup 13/CClF/sub 3/, respectively. To the first-order, the presence of chlorine isotopes would not affect the fractionation of carbon isotopes by the distillation of CClF/sub 3/. (auth)
Item Description:Published through SciTech Connect.
08/01/1975.
"coo-3127-11"
Ishida, T.; Wieck, H. J.
Brooklyn Coll., N.Y. (USA)
Physical Description:Pages: 148 : digital, PDF file.

Similar Items