The vapor pressure of /sup 13/CHF/sub 3/ relative to /sup 12/CHF/sub 3/ has been measured from 161 to 205/sup 0/K using a modified Bigeleisen distillation column and chromatography and mass spectroscopy of the oxidized samples. The data of each distillation run were reduced in light of a modified Cohen's theory of the kinetics of a square cascade of close-separation stages. The vapor pressure isotope effect for carbon substitution in CHF/sub 3/ in this temperature range was found to be an inverse effect. A trend of increasing inverse effect. A trend of increasing inverse effect with decreasing temperature has been observed. …
continued below
Serving as both a federal and a state depository library, the UNT Libraries Government Documents Department maintains millions of items in a variety of formats. The department is a member of the FDLP Content Partnerships Program and an Affiliated Archive of the National Archives.
Descriptive information to help identify this report.
Follow the links below to find similar items on the Digital Library.
Description
The vapor pressure of /sup 13/CHF/sub 3/ relative to /sup 12/CHF/sub 3/ has been measured from 161 to 205/sup 0/K using a modified Bigeleisen distillation column and chromatography and mass spectroscopy of the oxidized samples. The data of each distillation run were reduced in light of a modified Cohen's theory of the kinetics of a square cascade of close-separation stages. The vapor pressure isotope effect for carbon substitution in CHF/sub 3/ in this temperature range was found to be an inverse effect. A trend of increasing inverse effect. A trend of increasing inverse effect with decreasing temperature has been observed. The relative vapor pressure may be expressed as ln P'/P = (217 +- 66)/T - (0.89 +- 0.36)/T, where P' and P are the vapor pressures of /sup 12/CHF/sub 3/ and /sup 13/CHF/sub 3/ respectively. A cell model liquid force field for trifluoromethane is derived and the F matrix elements fit to the observed vapor pressure isotope effect are tabulated. 37 tables, 32 fig. (DLC)
This report is part of the following collection of related materials.
Office of Scientific & Technical Information Technical Reports
Reports, articles and other documents harvested from the Office of Scientific and Technical Information.
Office of Scientific and Technical Information (OSTI) is the Department of Energy (DOE) office that collects, preserves, and disseminates DOE-sponsored research and development (R&D) results that are the outcomes of R&D projects or other funded activities at DOE labs and facilities nationwide and grantees at universities and other institutions.
Borodinsky, L. & Ishida, T.Studies of carbon-13 vapor pressure isotope effect in CHF/sub 3/,
report,
August 1, 1976;
United States.
(https://digital.library.unt.edu/ark:/67531/metadc1443937/:
accessed May 6, 2024),
University of North Texas Libraries, UNT Digital Library, https://digital.library.unt.edu;
crediting UNT Libraries Government Documents Department.
