Isochoric pVT and phase equilibrium measurements for carbon dioxide + nitrogen

Journal Article · Mon May 01 04:00:00 EDT 1995 · Journal of Chemical and Engineering Data

DOI:https://doi.org/10.1021/je00019a038· OSTI ID:63347

Duarte-Garza, H A; Holste, J C; Hall, K R; Marsh, K N; Gammon, B E ^[1]

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1. Texas A and M Univ., College Station, TX (United States)

The authors have designed and constructed an isochoric apparatus for fast and accurate pressure-volume-temperature (pVT) and phase equilibrium measurements. The apparatus allows isochoric (p, T at constant V) measurements for noncorrosive fluids over a wide range of pressures (7--105 MPa) and temperatures (100--450 K). Densities can be derived from densities determined at one isotherm (p, V at constant T) with another apparatus, such as a pycnometer or a Burnett apparatus. Temperatures are accurate to {+-} 10 mK and precise to {+-}1 mK on ITS-90. Pressure measurements are accurate to {+-}10 kPa and precise to {+-}2 kPa. This apparatus requires about 20 min for temperature equilibration for measurements 2 K apart and about 50 min for measurements 10 K apart. The authors have measured 23 phase boundary points for three mole fractions, x{sub 1} = 0.3991, 0.4459, and 0.5037, for CO{sub 2} (1) + N{sub 2} (2) at temperatures from 207 to 268 K and pressures from 10.8 to 21.5 MPa. The estimated accuracy is {+-} 40 mK in temperature and {+-} 17 kPa in pressure. The isochoric measurements used to obtain these phase boundary points extend from 205 to 300 K and from 8 to 80 MPa. They have determined the saturation density for 20 of the phase boundary points. The saturation densities and the densities along the isochores were derived from density measurements at 300 and 285 K measured with a pycnometer estimated to be accurate to {+-}0.1%. The behavior of the solid + fluid phase boundary is discussed.

• Sponsoring Organization: USDOE
• OSTI ID: 63347
• Journal Information: Journal of Chemical and Engineering Data, Journal Name: Journal of Chemical and Engineering Data Journal Issue: 3 Vol. 40; ISSN JCEAAX; ISSN 0021-9568
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
BINARY MIXTURES
CARBON DIOXIDE
DENSITY
DESIGN
MEASURING INSTRUMENTS
NITROGEN
PHASE STUDIES
PRESSURE MEASUREMENT
TEMPERATURE MEASUREMENT
THERMODYNAMIC PROPERTIES