Thermodynamics of liquid (nitrogen + ethane)

Guedes, Henrique J. R.; Zollweg, John A.; Filipe, Eduardo J. M.; Martins, Luís F. G.; Calado, Jorge C. G.

doi:10.1006/jcht.2001.0936

Cited by 17 publications

(3 citation statements)

References 9 publications

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“…Table presents the list of pure components used in this study. The pure fluid physical properties ( T c , P c , and ω) used in this study originate from Poling et al Table details the sources of the binary experimental data used in our evaluations, − …”

Section: The Ppr78 Modelmentioning

confidence: 99%

Addition of the Nitrogen Group to the PPR78 Model (Predictive 1978, Peng Robinson EOS with Temperature-Dependent k_ij Calculated through a Group Contribution Method)

Privat¹,

Jaubert²,

Mutelet³

2008

Ind. Eng. Chem. Res.

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In 2004, we started to develop a group contribution method aimed at estimating the temperature-dependent binary interaction parameters (k ij (T)) for the widely used Peng−Robinson equation of state (EOS). This model was called PPR78 (predictive 1978, Peng Robinson EOS), because it relies on the Peng−Robinson EOS as published by Peng and Robinson in 1978 and because the addition of a group contribution method to estimate the k ij value makes it predictive. In our previous papers, 12 groups were defined: CH3, CH2, CH, C, CH4 (methane), C2H6 (ethane), CHaro, Caro, Cfused aromatic rings, CH2,cyclic, CHcyclic = Ccyclic, and CO2. Thus, it was possible to estimate the k ij value for any mixture that contains alkanes, aromatics, naphthenes, and CO2, regardless of the temperature. In this study, the PPR78 model is extended to systems that contain nitrogen. To do so, the group N2 was added.

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Section: The Ppr78 Modelmentioning

confidence: 99%

Addition of the Nitrogen Group to the PPR78 Model (Predictive 1978, Peng Robinson EOS with Temperature-Dependent k_ij Calculated through a Group Contribution Method)

Privat¹,

Jaubert²,

Mutelet³

2008

Ind. Eng. Chem. Res.

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“…Nitrogen-hydrocarbon mixtures are important not only for the testing and extension of fluid mixture theories but also for many engineering processes like the separation and refinement of natural gas. Most researches are dedicated to VLE; however, VLLE are also considered and published data on nitrogen-ethane (Guedes et al, 2002;Llave et al, 1985;Raabe and Kohler, 2004;Romig and Hanley, 1986), nitrogen-ethylene (Gasem et al, 1981), and nitrogen-propane (Houssin-Agbomson et al, 2010;Llave et al, 1985) mixtures are also available.…”

Section: Introductionmentioning

confidence: 99%

Modeling of vapor–liquid–liquid equilibria in binary mixtures

Tzabar

Brake

2016

International Journal of Refrigeration

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“…While adiabatic calorimeters are recognized as the most accurate method for heat capacity measurements at low temperature, they are poorly suited for measurements at high pressure and often require skillful operation and/or have less versatility than other calorimeters. Flow calorimeters have been used for heat capacity measurements on liquids at low temperature , and have the advantage of rapidly making measurements at one temperature on mixtures over the composition range, but large sample volumes are required, particularly for measurements over a temperature range. Differential scanning calorimetry is one of the most versatile techniques for heat capacity and enthalpy of fusion measurements with many commercial apparatus available, and it has been demonstrated recently that accurate heat capacities for liquids can be measured by DSC systems if large samples and slow scan rates are used. , To minimize the degree of instrument development required to acquire new c p data for cryogenic liquids at high-pressures, we chose to base our specialized calorimeter on a commercially available DSC and modify it as necessary to achieve the functionality required.…”

Section: Introductionmentioning

confidence: 99%

Isobaric Heat Capacity Measurements of Liquid Methane, Ethane, and Propane by Differential Scanning Calorimetry at High Pressures and Low Temperatures

et al. 2012

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A commercial differential scanning calorimeter (DSC) was adapted to allow accurate isobaric heat capacity, c p , measurements of cryogenic, high-pressure liquids. At (subcritical) temperatures between (108.15 and 258.15) K and pressures between (1.1 and 6.35) MPa, the standard deviation in the measured c p values was 0.005·c p for methane, 0.01·c p for ethane, and 0.015·c p for propane, which is comparable to both the scatter of c p data for these liquids measured using other techniques and with the scatter of those data sets about the reference equation of state (EOS) values. Three key modifications to the commercial DSC were required to enable these accurate cryogenic, high-pressure liquid c p measurements. First, methods of loading and removing the liquid from the calorimeter without moving the sample cell were developed and tested with high boiling temperature liquids; this modification improved the measurement repeatability. Second, a ballast volume containing a high-pressure vapor phase at constant temperature was connected to the DSC cell so that the liquid sample’s thermal expansion did not cause significant changes in pressure. A third modification was required because the boil-off vapor from the liquid nitrogen used to cool the calorimeter resulted in a temperature inversion, and hence convection, along the tubing connecting the DSC’s sample cell to the ballast volume, that lead to an unstable calorimetric signal at T > 130 K. The modifications to the specialized DSC were tested by measuring c p values for heptane, methylbenzene, and a heptane (1) + methylbenzene (2) mixture with x 1 = 0.38 at atmospheric pressure and temperatures of (228.15, 238.15, 303.15, and 313.15) K. The measured values had relative deviations from those measured adiabatically by Holzhauer and Ziegler (J. Phys. Chem. 1975, 79, 590–604) of less than 0.006·c p , indicating that the specialized DSC could be used for liquids and liquid mixtures at conditions relevant to liquefied natural gas production.

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Thermodynamics of liquid (nitrogen + ethane)

Cited by 17 publications

References 9 publications

Addition of the Nitrogen Group to the PPR78 Model (Predictive 1978, Peng Robinson EOS with Temperature-Dependent k_ij Calculated through a Group Contribution Method)

Addition of the Nitrogen Group to the PPR78 Model (Predictive 1978, Peng Robinson EOS with Temperature-Dependent k_ij Calculated through a Group Contribution Method)

Modeling of vapor–liquid–liquid equilibria in binary mixtures

Isobaric Heat Capacity Measurements of Liquid Methane, Ethane, and Propane by Differential Scanning Calorimetry at High Pressures and Low Temperatures

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Thermodynamics of liquid (nitrogen + ethane)

Cited by 17 publications

References 9 publications

Addition of the Nitrogen Group to the PPR78 Model (Predictive 1978, Peng Robinson EOS with Temperature-Dependent kij Calculated through a Group Contribution Method)

Addition of the Nitrogen Group to the PPR78 Model (Predictive 1978, Peng Robinson EOS with Temperature-Dependent kij Calculated through a Group Contribution Method)

Modeling of vapor–liquid–liquid equilibria in binary mixtures

Isobaric Heat Capacity Measurements of Liquid Methane, Ethane, and Propane by Differential Scanning Calorimetry at High Pressures and Low Temperatures

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Product

Resources

About

Addition of the Nitrogen Group to the PPR78 Model (Predictive 1978, Peng Robinson EOS with Temperature-Dependent k_ij Calculated through a Group Contribution Method)

Addition of the Nitrogen Group to the PPR78 Model (Predictive 1978, Peng Robinson EOS with Temperature-Dependent k_ij Calculated through a Group Contribution Method)