Evaluating Characteristic Parameters for Carbon Dioxide in the Sanchez−Lacombe Equation of State
Loading...
Date
2017
Authors
von Konigslow, Kier
Park, Chul B.
Thompson, Russell B.
Journal Title
Journal ISSN
Volume Title
Publisher
American Chemical Society
Abstract
For many different pure substances, large numbers of competing
characteristic parameter sets exist in the literature for the Sanchez−Lacombe equation
of state. This is due in part to differing research requirements or differing procedures
used for determining the parameters. The existing parameters for carbon dioxide are
reviewed in order to determine whether a single set of parameters can describe the
equation of state over large ranges of temperature and pressure. It is found that by
consideration of a large collection of experiments, a good fit can be achieved over
much larger temperature and pressure ranges than previously thought possible.
Properties directly related to the equation of state, such as the thermal expansivity and
isothermal compressibility, are also predicted well; however, as expected, properties
that depend on the internal degrees of freedom of molecules, such as the specific heats,
do not correlate well. Closely agreeing parameter sets are found in the literature that fit
the equation of state data reasonably well over a large range. A new set of parameters is found using a least-squares approach over the largest ranges of temperature and pressure to date. These parameters are found to be P* = 419.9 MPa, T* = 341.8 K, and ρ*= 1.397 g/cm3 using N = 556 experimental data points over the temperature range of 216.58−1800 K and the pressure range of 0.5−66.57 MPa.
Description
This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of Chemical & Engineering Data, copyright © American Chemical Society after peer review and technical editing by publisher. To access the final edited and published work see https://doi.org/10.1021/acs.jced.6b00743
Keywords
carbon dioxide, equations of state, Sanchez-Lacombe, polymer foams