Alain Valtz - Academia.edu (original) (raw)
Papers by Alain Valtz
Industrial & Engineering Chemistry Research, Mar 9, 2011
Hydrofluoroalkenes, like hexafluoropropylene, can be considered as new fluids for refrigeration s... more Hydrofluoroalkenes, like hexafluoropropylene, can be considered as new fluids for refrigeration systems, and consequently volumetric and critical property data are required. In this study a vibrating-tube densitometer technique was used to determine densities at 10 different temperatures between (263 and 362) K and pressures between (0.0009 and 10) MPa. The experimental uncertainties are (0.0005 MPa for pressure, (0.02 K for the temperature, and (0.05 % for vapor and liquid densities. Critical properties have been determined by direct measurement and utilization of experimental densities considering scaling laws. The Wagner, Span and Wagner, Peng-Robinson, and translated Peng-Robinson equations of state are used to correlate the data.
International Journal of Refrigeration
Journal of Chemical & Engineering Data, 2021
International Journal of Petroleum Technology, 2021
In this work, new isothermal experimental data of vapor-liquid equilibrium of the isobutane and e... more In this work, new isothermal experimental data of vapor-liquid equilibrium of the isobutane and ethyl mercaptan binary system are presented. The pressure and temperature conditions are up to 1 MPa and between 298 and 343K. The experimental apparatus is based on a “static-analytic method” specially developed for low-pressure measurements. Two online capillary samplers are used to take vapor and liquid samples that are analyzed with a gas chromatograph. The classical Peng Robinson Equation of State is used to correlate the experimental data. The van Ness test is used to check the consistency of the data. The measured data are also compared to predicted values from two predictive models, and a good agreement is found between the PSRK UNIFAC and the PPR78 models and the experimental measurements.
Journal of Chemical & Engineering Data, 2020
U min ()= 0.2 kg.m-3 U max ()= 8 kg.m-3 U min ()= 0.5 kg.m-3 U max ()= 15 kg.m-3 U min ()= 0... more U min ()= 0.2 kg.m-3 U max ()= 8 kg.m-3 U min ()= 0.5 kg.m-3 U max ()= 15 kg.m-3 U min ()= 0.4 kg.m-3 U max ()= 13 kg.m-3 U min ()= 0.1 kg.m-3 U max ()= 3 kg.m-3 U min ()= 0.1 kg.m-3 U max ()= 3 kg.m-3 U min ()= 0.1 kg.m-3 U max ()= 2 kg.m-3 U min ()= 0.2 kg.m-3 U max ()= 5 kg.m-3 U min ()= 0.1kg.m-3 U max ()= 2.5 kg.m-3 p/MPa /kg.m-3 p/MPa /kg.m-3 p/MPa /kg.m-3 p/MPa /kg.m-3 p/MPa /kg.m-3 p/MPa /kg.m-3 p/MPa /kg.m-3 p/MPa /kg.m-3
Journal of Chemical & Engineering Data, 2020
The study presents p-T-x-y phase equilibria measurements of one solvent, chlorobenzene and one so... more The study presents p-T-x-y phase equilibria measurements of one solvent, chlorobenzene and one solute, hydrogen chloride. The technique of the equipment used is based on a "static-analytic" method that takes advantages of two capillary samplers linked to a gas chromatograph. Measurements were done at three temperatures (353.16, 403.16 and 453.25 K) and pressures from 0.6 up to 6.5 MPa. The experimental data measured were successfully correlated using the Peng Robinson Equation of state.
Fluid Phase Equilibria, 2019
Journal of Chemical & Engineering Data, 2018
International Journal of Refrigeration, 2019
Journal of Natural Gas Engineering, 2019
Fluid Phase Equilibria, 2016
Fluid Phase Equilibria, 2016
Fluid Phase Equilibria, 2016
Fluid Phase Equilibria, 2014
Fluid Phase Equilibria, 2014
Journal of Chemical & Engineering Data, 2003
Isothermal vapor-liquid equilibrium data for the Difluoromethane (R32) + Propane binary system ar... more Isothermal vapor-liquid equilibrium data for the Difluoromethane (R32) + Propane binary system are presented at 278.10, 294.83, 303.23, 313.26 and 343.26 K and pressures up to 5.4 MPa. The experimental method is the static-analytic type. It takes advantage of mobile pneumatic capillary samplers (Rolsi™, Armines' patent) developed in our laboratory. At a fixed temperature the azeotrope vapor pressure is larger then those of the pure component. The particularity of R32-Propane azeotropic binary system is to present in two critical point over the critical temperature if the azeotrope. This particular behavior has been proved and even shown visually by means of two supplementary experiments with equipment based on the static-synthetic method involving a variable volume cell. Data along the five isotherms have been represented with the Soave-Redlich-Kwong (SRK) equation of state and MHV1 mixing rules involving the NRTL model. We have calculated the location of the azeotrope using the equality of Equation of State attractive parameter between the two phases.
Industrial & Engineering Chemistry Research, 2011
... Modeling In a previous paper,(3) we used the Peng−Robinson equation of state (PR EoS)(13) wit... more ... Modeling In a previous paper,(3) we used the Peng−Robinson equation of state (PR EoS)(13) with the Mathias−Copeman (MC)(14) alpha function to correlate the vapor pressure and the densities of HFP. ... That is why, in this work, it is specified Landau-crossover. ...
Industrial & Engineering Chemistry Research, 2011
En référence à 1) Comments on "Experimental Measurement of Vapor Pressures and Densities at ... more En référence à 1) Comments on "Experimental Measurement of Vapor Pressures and Densities at Saturation of Pure Hexafluoropropylene Oxide: Modeling Using a Crossover Equation of State" Author(s): Laugier, Serge; Richon, Dominique Source: INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH Volume: 50 Issue: 15 Special Issue: SI Pages: 9473-9475 DOI: 10.1021/ie2011559 Published: AUG 3 2011 2) Experimental Measurement of Vapor Pressures and Densities at Saturation of Pure Hexafluoropropylene Oxide: Modeling Using a Crossover Equation of State Author(s): Dicko, Moussa; Belaribi-Boukais, Ghemina; Coquelet, Christophe; Valtz, Alain; Belaribi, Farid Brahim; Naidoo, Paramespri; Ramjugernath, Deresh Source: INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH Volume: 50 Issue: 8 Pages: 4761-4768 DOI: 10.1021/ie102354p Published: APR 20 2011International audienc
Industrial & Engineering Chemistry Research, Mar 9, 2011
Hydrofluoroalkenes, like hexafluoropropylene, can be considered as new fluids for refrigeration s... more Hydrofluoroalkenes, like hexafluoropropylene, can be considered as new fluids for refrigeration systems, and consequently volumetric and critical property data are required. In this study a vibrating-tube densitometer technique was used to determine densities at 10 different temperatures between (263 and 362) K and pressures between (0.0009 and 10) MPa. The experimental uncertainties are (0.0005 MPa for pressure, (0.02 K for the temperature, and (0.05 % for vapor and liquid densities. Critical properties have been determined by direct measurement and utilization of experimental densities considering scaling laws. The Wagner, Span and Wagner, Peng-Robinson, and translated Peng-Robinson equations of state are used to correlate the data.
International Journal of Refrigeration
Journal of Chemical & Engineering Data, 2021
International Journal of Petroleum Technology, 2021
In this work, new isothermal experimental data of vapor-liquid equilibrium of the isobutane and e... more In this work, new isothermal experimental data of vapor-liquid equilibrium of the isobutane and ethyl mercaptan binary system are presented. The pressure and temperature conditions are up to 1 MPa and between 298 and 343K. The experimental apparatus is based on a “static-analytic method” specially developed for low-pressure measurements. Two online capillary samplers are used to take vapor and liquid samples that are analyzed with a gas chromatograph. The classical Peng Robinson Equation of State is used to correlate the experimental data. The van Ness test is used to check the consistency of the data. The measured data are also compared to predicted values from two predictive models, and a good agreement is found between the PSRK UNIFAC and the PPR78 models and the experimental measurements.
Journal of Chemical & Engineering Data, 2020
U min ()= 0.2 kg.m-3 U max ()= 8 kg.m-3 U min ()= 0.5 kg.m-3 U max ()= 15 kg.m-3 U min ()= 0... more U min ()= 0.2 kg.m-3 U max ()= 8 kg.m-3 U min ()= 0.5 kg.m-3 U max ()= 15 kg.m-3 U min ()= 0.4 kg.m-3 U max ()= 13 kg.m-3 U min ()= 0.1 kg.m-3 U max ()= 3 kg.m-3 U min ()= 0.1 kg.m-3 U max ()= 3 kg.m-3 U min ()= 0.1 kg.m-3 U max ()= 2 kg.m-3 U min ()= 0.2 kg.m-3 U max ()= 5 kg.m-3 U min ()= 0.1kg.m-3 U max ()= 2.5 kg.m-3 p/MPa /kg.m-3 p/MPa /kg.m-3 p/MPa /kg.m-3 p/MPa /kg.m-3 p/MPa /kg.m-3 p/MPa /kg.m-3 p/MPa /kg.m-3 p/MPa /kg.m-3
Journal of Chemical & Engineering Data, 2020
The study presents p-T-x-y phase equilibria measurements of one solvent, chlorobenzene and one so... more The study presents p-T-x-y phase equilibria measurements of one solvent, chlorobenzene and one solute, hydrogen chloride. The technique of the equipment used is based on a "static-analytic" method that takes advantages of two capillary samplers linked to a gas chromatograph. Measurements were done at three temperatures (353.16, 403.16 and 453.25 K) and pressures from 0.6 up to 6.5 MPa. The experimental data measured were successfully correlated using the Peng Robinson Equation of state.
Fluid Phase Equilibria, 2019
Journal of Chemical & Engineering Data, 2018
International Journal of Refrigeration, 2019
Journal of Natural Gas Engineering, 2019
Fluid Phase Equilibria, 2016
Fluid Phase Equilibria, 2016
Fluid Phase Equilibria, 2016
Fluid Phase Equilibria, 2014
Fluid Phase Equilibria, 2014
Journal of Chemical & Engineering Data, 2003
Isothermal vapor-liquid equilibrium data for the Difluoromethane (R32) + Propane binary system ar... more Isothermal vapor-liquid equilibrium data for the Difluoromethane (R32) + Propane binary system are presented at 278.10, 294.83, 303.23, 313.26 and 343.26 K and pressures up to 5.4 MPa. The experimental method is the static-analytic type. It takes advantage of mobile pneumatic capillary samplers (Rolsi™, Armines' patent) developed in our laboratory. At a fixed temperature the azeotrope vapor pressure is larger then those of the pure component. The particularity of R32-Propane azeotropic binary system is to present in two critical point over the critical temperature if the azeotrope. This particular behavior has been proved and even shown visually by means of two supplementary experiments with equipment based on the static-synthetic method involving a variable volume cell. Data along the five isotherms have been represented with the Soave-Redlich-Kwong (SRK) equation of state and MHV1 mixing rules involving the NRTL model. We have calculated the location of the azeotrope using the equality of Equation of State attractive parameter between the two phases.
Industrial & Engineering Chemistry Research, 2011
... Modeling In a previous paper,(3) we used the Peng−Robinson equation of state (PR EoS)(13) wit... more ... Modeling In a previous paper,(3) we used the Peng−Robinson equation of state (PR EoS)(13) with the Mathias−Copeman (MC)(14) alpha function to correlate the vapor pressure and the densities of HFP. ... That is why, in this work, it is specified Landau-crossover. ...
Industrial & Engineering Chemistry Research, 2011
En référence à 1) Comments on "Experimental Measurement of Vapor Pressures and Densities at ... more En référence à 1) Comments on "Experimental Measurement of Vapor Pressures and Densities at Saturation of Pure Hexafluoropropylene Oxide: Modeling Using a Crossover Equation of State" Author(s): Laugier, Serge; Richon, Dominique Source: INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH Volume: 50 Issue: 15 Special Issue: SI Pages: 9473-9475 DOI: 10.1021/ie2011559 Published: AUG 3 2011 2) Experimental Measurement of Vapor Pressures and Densities at Saturation of Pure Hexafluoropropylene Oxide: Modeling Using a Crossover Equation of State Author(s): Dicko, Moussa; Belaribi-Boukais, Ghemina; Coquelet, Christophe; Valtz, Alain; Belaribi, Farid Brahim; Naidoo, Paramespri; Ramjugernath, Deresh Source: INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH Volume: 50 Issue: 8 Pages: 4761-4768 DOI: 10.1021/ie102354p Published: APR 20 2011International audienc