Orthobaric Liquid Densities of Normal Butane from 135 to 300 K as Determined with a Magnetic Suspension Densimeter
Of the principal constituents of natural gas, normal butane is the first in the series of paraffin hydrocarbons that has a triple-point temperature significantly higher than the normal boiling point (112 to 115 K) of methane-rich liquefied natural gas (LNG). Unlike isobutane, with a triple-point temperature (113.6 K) near the normal boiling point of methane-rich LNG, normal butane freezes at the relatively high temperature of 134.8 K. Thus any estimate of the contribution of n-butane content to the molar volume (or molar density) of LNG requires a relatively long extrapolation into the subcooled liquid region of n-butane. It is also known that n-butane is the first in the series of paraffin hydrocarbons exhibiting geometrical isomerism, with nearly instantaneous equilibrium, which contributes to the temperature dependence of the molar density [1–5]. It follows that an analytical expression that provides the most reliable means of extrapolating n-butane densities into the subcooled liquid region cannot be based on correspondence alone, but must be based on extensive and accurate data above the triple-point temperature.
KeywordsLiquid Density Barium Ferrite Normal Boiling Point Molar Density Paraffin Hydrocarbon
Unable to display preview. Download preview PDF.
- 4.M. R. Cines, Phillips Petroleum Co., private communication (January 1974).Google Scholar
- 5.T. W. Schmidt, Phillips Petroleum Co., private communication (May 1974).Google Scholar
- 8.J. Klosek and C. McKinley, in: Proceedings of First Intern. Conference on LNG, Chicago, Illinois (1968), Paper 22, Session 5.Google Scholar
- 10.W. M. Haynes, N. V. Frederick, and M. J. Hiza, unpublished data.Google Scholar
- 11.A. F. Clark, W. M. Haynes, V. A. Deason, and R. J. Trapani, Cryogenics (to be published).Google Scholar
- 13.Natural Gas Processors Supplies Association, Engineering Data Book, Ninth Edition, NGPA, Tulsa, Oklahoma (1972).Google Scholar
- 14.American Petroleum Institute, Project 44, Selected Values of Physical and Thermodynamic Properties of Hydrocarbons and Related Compounds, Carnegie Press, Pittsburgh, Pennsylvania (1953).Google Scholar