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Julien Andrieu - One of the best experts on this subject based on the ideXlab platform.

  • Implementation and validation of the thermogravimetric method for the determination of Equilibrium vapour pressure values and sublimation enthalpies of frozen organic formulations used in drug freeze-drying processes
    Chemical Engineering Research and Design, 2011
    Co-Authors: Eni Bogdani, Rim Daoussi, Séverine Vessot, Jacques Jose, Julien Andrieu
    Abstract:

    he modelling of the sublimation step needs the knowledge of basic thermodynamic properties as the Equilibrium solid-vapour pressures and the sublimation enthalpies. Unfortunately these thermodynamic properties are generally missing in the literature. Tert-butanol (TBA) co-solvent has been used largely as solvent in freeze-drying formulation. Thus, in the present study, we have determined the Equilibrium values of vapour pressures (solid-vapour and Liquid-Vapour Equilibrium) and sublimation enthalpies of pure TBA and for its eutectic mixture with water, namely the 90% (w/w) TBA + 10% (w/w) mixture, by using two different and comparative methods: the Thermogravimetric Method crc Method) and the Static Method. TG experiments were conducted in dynamic conditions in a temperature range from -30 degrees C to 80 degrees C. Both methods led to similar values with a relative deviation less than 2%. This validation proved that the TG method is a rapid, reliable and precise technique for the determination of solid/vapour and liquid/vapour Equilibrium pressures for pure substances or for co-solvent + water mixtures at eutectic/azeotropic compositions.

  • Implementation and validation of the thermogravimetric method for the determination of Equilibrium vapour pressure values and sublimation enthalpies of frozen organic formulations used in drug freeze–drying processes
    Chemical Engineering Research and Design, 2011
    Co-Authors: Eni Bogdani, Rim Daoussi, Séverine Vessot, Jacques Jose, Julien Andrieu
    Abstract:

    International audiencehe modelling of the sublimation step needs the knowledge of basic thermodynamic properties as the Equilibrium solid-vapour pressures and the sublimation enthalpies. Unfortunately these thermodynamic properties are generally missing in the literature. Tert-butanol (TBA) co-solvent has been used largely as solvent in freeze-drying formulation. Thus, in the present study, we have determined the Equilibrium values of vapour pressures (solid-vapour and Liquid-Vapour Equilibrium) and sublimation enthalpies of pure TBA and for its eutectic mixture with water, namely the 90% (w/w) TBA + 10% (w/w) mixture, by using two different and comparative methods: the Thermogravimetric Method crc Method) and the Static Method. TG experiments were conducted in dynamic conditions in a temperature range from -30 degrees C to 80 degrees C. Both methods led to similar values with a relative deviation less than 2%. This validation proved that the TG method is a rapid, reliable and precise technique for the determination of solid/vapour and liquid/vapour Equilibrium pressures for pure substances or for co-solvent + water mixtures at eutectic/azeotropic compositions

Eni Bogdani - One of the best experts on this subject based on the ideXlab platform.

  • Implementation and validation of the thermogravimetric method for the determination of Equilibrium vapour pressure values and sublimation enthalpies of frozen organic formulations used in drug freeze-drying processes
    Chemical Engineering Research and Design, 2011
    Co-Authors: Eni Bogdani, Rim Daoussi, Séverine Vessot, Jacques Jose, Julien Andrieu
    Abstract:

    he modelling of the sublimation step needs the knowledge of basic thermodynamic properties as the Equilibrium solid-vapour pressures and the sublimation enthalpies. Unfortunately these thermodynamic properties are generally missing in the literature. Tert-butanol (TBA) co-solvent has been used largely as solvent in freeze-drying formulation. Thus, in the present study, we have determined the Equilibrium values of vapour pressures (solid-vapour and Liquid-Vapour Equilibrium) and sublimation enthalpies of pure TBA and for its eutectic mixture with water, namely the 90% (w/w) TBA + 10% (w/w) mixture, by using two different and comparative methods: the Thermogravimetric Method crc Method) and the Static Method. TG experiments were conducted in dynamic conditions in a temperature range from -30 degrees C to 80 degrees C. Both methods led to similar values with a relative deviation less than 2%. This validation proved that the TG method is a rapid, reliable and precise technique for the determination of solid/vapour and liquid/vapour Equilibrium pressures for pure substances or for co-solvent + water mixtures at eutectic/azeotropic compositions.

  • Implementation and validation of the thermogravimetric method for the determination of Equilibrium vapour pressure values and sublimation enthalpies of frozen organic formulations used in drug freeze–drying processes
    Chemical Engineering Research and Design, 2011
    Co-Authors: Eni Bogdani, Rim Daoussi, Séverine Vessot, Jacques Jose, Julien Andrieu
    Abstract:

    International audiencehe modelling of the sublimation step needs the knowledge of basic thermodynamic properties as the Equilibrium solid-vapour pressures and the sublimation enthalpies. Unfortunately these thermodynamic properties are generally missing in the literature. Tert-butanol (TBA) co-solvent has been used largely as solvent in freeze-drying formulation. Thus, in the present study, we have determined the Equilibrium values of vapour pressures (solid-vapour and Liquid-Vapour Equilibrium) and sublimation enthalpies of pure TBA and for its eutectic mixture with water, namely the 90% (w/w) TBA + 10% (w/w) mixture, by using two different and comparative methods: the Thermogravimetric Method crc Method) and the Static Method. TG experiments were conducted in dynamic conditions in a temperature range from -30 degrees C to 80 degrees C. Both methods led to similar values with a relative deviation less than 2%. This validation proved that the TG method is a rapid, reliable and precise technique for the determination of solid/vapour and liquid/vapour Equilibrium pressures for pure substances or for co-solvent + water mixtures at eutectic/azeotropic compositions

J. De Swaan Arons - One of the best experts on this subject based on the ideXlab platform.

  • High-pressure phase equilibria in the systems methane + phenanthrene and methane + 1-phenyldodecane up to 400 MPa
    Fluid Phase Equilibria, 1997
    Co-Authors: Eckhard Flöter, Th.w. De Loos, P. Van Der Pijl, J. De Swaan Arons
    Abstract:

    Abstract In this paper, experimental data on the high-pressure phase behaviour of the systems methane + phenanthrene and methane + 1-phenyldodecane are presented. For both systems vapour-liquid, solid-fluid, and solid-Liquid-Vapour Equilibrium data were determined. The experiments were carried out for various mixtures covering almost the whole composition range. The temperature range investigated was from 360 to 460 K for the methane + phenanthrene system and from 260 to 400 K for the methane + 1-phenyldodecane system. The maximum pressures exerted on the samples were dependent on the equipment used, either 200 or 400 MPa. The second critical endpoint (s + 1 = g), which is the pressure maximum of the three-phase curve (solid hydrocarbon + liquid + vapour), is, for the methane + phenanthrene system, located at a temperature T = 403.3 ± 0.4 K, a pressure p = 358.9 ± 1.5 MPa, and a mole fraction of phenanthrene in the critical fluid phase x = 0.126 ± 0.009. The coordinates of the second critical endpoint of the methane + 1-phenyldodecane system were found to be T = 277.1 ± 0.4 K, p = 148.0 ± 0.6 MPa, and for the mole fraction of 1-phenyldodecane in the critical fluid phase x = 0.076 ± 0.005.

  • High pressure solid-fluid and vapour-liquid equilibria in the system (methane + tetracosane)
    Fluid Phase Equilibria, 1997
    Co-Authors: Eckhard Flöter, Th.w. De Loos, J. De Swaan Arons
    Abstract:

    Abstract Experimental vapour-liquid, solid-fluid, and solid-Liquid-Vapour Equilibrium data of the binary system (methane + tetracosane) in the temperature range 315–450 K and for pressures up to 200 MPa are presented. The experiments were carried out for various mixtures with compositions ranging from almost pure methane to pure tetracosane. It was found that the (solid α-to-solidβ) transition of pure tetracosane has hardly any influence on the shape of the (solid + fluid/fluid) boundary curves and the three-phase Equilibrium curve (solid tetracosane + liquid + vapour) of the binary system. The second critical endpoint of the three-phase curve (sC24 + 1 = g), where solid tetracosane is in Equilibrium with a critical fluid phase was located at a temperature of T = (322.60 ± 0.25)K, a pressure of p = (104.7 ± 0.4)MPa, and a mole fraction of tetracosane in the critical fluid phase of xC24 = (0.041 ± 0.003).

  • Liquid-Liquid-Vapour Phase Equilibria in the System Methane + Ethane + Eicosane: Precision in Establishing Complex Phase Behaviour
    Precision Process Technology, 1993
    Co-Authors: P.j. Smits, J. Gregorowicz, Th.w. De Loos, J. De Swaan Arons
    Abstract:

    Liquid-Liquid-Vapour Equilibrium experiments were conducted with model reservoir fluids comprising the ternary system methane + ethane + eicosane, with special emphasis on retrograde condensation of the second, heavier liquid phase. P,T-sections for mixtures of constant composition were determined according to the synthetic method for several constant molar ratios of ethane and eicosane and different mole fractions of methane. The temperature range investigated was 290–307 K and the pressure range 5.0–6.4 MPa. Some of the mixtures studied were found to exhibit retrograde condensation of the heavier liquid phase over a narrow range of temperature and concentration of eicosane.

Peiyu Yang - One of the best experts on this subject based on the ideXlab platform.

  • A temperature-dependent potential model for mercury in the description of vapour-liquid Equilibrium & adsorption in activated carbon
    Chemical Engineering Science, 2020
    Co-Authors: Xiu Liu, Chunyan Fan, Duong D., Vishnu Pareek, Peiyu Yang
    Abstract:

    Abstract A practical potential equation for mercury was developed, by incorporating the long-ranged interaction and multi-body effects into the temperature-dependent dispersion parameters, to describe the thermodynamic properties of the Liquid-Vapour Equilibrium and adsorption in carbonaceous materials. The collision diameter (σ) decreases and the well depth of interaction energy (e) increases with temperature, with the product σ6e (a measure of attraction) decreasing with temperature. The critical temperature derived from this model, 1745 K, agrees well with the experimental value of 1751 K, and the wetting temperature of mercury on graphite was found to be 1600 K, supporting the fact that mercury does not wet carbon under ambient conditions. Furthermore, it was illustrated with mercury can fill ultrafine graphitic slit pores, whose widths less than 0.7 nm, under ambient temperatures, because of the enhancement of the solid-fluid potential and the strong intermolecular interactions, and the simulation results qualitatively agree well with experimental data.

Pál Jedlovszky - One of the best experts on this subject based on the ideXlab platform.

  • Vapour-liquid Equilibrium of acetone-CO2 mixtures of different compositions at the vicinity of the critical point
    Journal of CO2 Utilization, 2019
    Co-Authors: Balázs Fábián, George Horvai, Abdenacer Idrissi, Pál Jedlovszky
    Abstract:

    Abstract The vapour-liquid Equilibrium of acetone−CO2 mixtures is studied by computer simulation at 11 different compositions, ranging from neat CO2 to neat acetone, in a 50–100 K wide range of temperatures at the vicinity of the critical point. The composition dependence of the critical parameters is determined, for the first time, in the entire composition range. It is found that while the critical temperature changes monotonically with the composition, the critical pressure goes through a maximum around the acetone mole fraction value of 0.3, and the critical density might also exhibit a maximum in the acetone mole fraction range of 0-0.2. Temperature dependence of the surface tension is also determined in the entire composition range. The obtained results agree, in general, well with experimental data; their deviation remains below the range within which different experimental data sets deviate from each other. Since experimental data in this respect exist, unfortunately, only in limited ranges of compositions (at low acetone mole fractions) and temperatures (data above about 335 K are scarce), the present study largely extends the range of thermodynamic conditions in which we have reliable information on the Liquid-Vapour Equilibrium and critical conditions of acetone−CO2 mixtures.