Fractionnement par CO2 supercritique de mélanges modèles. Etude expérimentale multi-échelles et modélisation (thèse 2018 - 2021 soutenue au M2P2)
Activités
modélisation de procédé,
changement d'échelle.
Publications scientifiques au M2P2
2024
Aymeric Fabien, Guillaume Lefebvre, Elisabeth Badens, Brice Calvignac, Damien Chaudanson, et al.. Contact angle of ethanol, water, and their mixtures on stainless steel surfaces in dense carbon dioxide. Journal of Colloid and Interface Science, 2024, 655, pp.535-545. ⟨10.1016/j.jcis.2023.10.163⟩. ⟨hal-04316090⟩ Plus de détails...
Hypothesis Contact angle can be a key parameter in chemical engineering. However, the development and the optimization of numerous processes using supercritical CO2, considered as environmentally friendly, requires new measurements under dense CO2 atmosphere. Besides, the influence of the roughness or the wetting regime on the contact angle is known at ambient conditions but remains to be discussed for systems under high pressure. Experimental Contact angle measurements of ethanol, water, and their mixtures, with ethanol mass fractions ranging from 0.25 to 0.75, on two stainless steels in saturated CO2 at pressures ranging from 0.1 MPa to 15.1 MPa, and at 313 K and 333 K were carried out in a set-up improving mass transfer between the studied liquid and the continuous fluid phase. Stainless steel surfaces have been characterized by atomic force and scanning electron microscopies allowing the application of the Wenzel equation. Findings Ethanol wetted totally both stainless steels while contact angles of all other liquids were increased by the rise of pressure, with contact angles up to 128 ° for water at 15.1 MPa. Trapped bubbles were observed at the solid/liquid interface and the bubble formation is discussed. Furthermore, the potential influence of bubble presence on the wetting regime is prospected through the question: could the pressure rise modify the wetting regime?
Aymeric Fabien, Guillaume Lefebvre, Elisabeth Badens, Brice Calvignac, Damien Chaudanson, et al.. Contact angle of ethanol, water, and their mixtures on stainless steel surfaces in dense carbon dioxide. Journal of Colloid and Interface Science, 2024, 655, pp.535-545. ⟨10.1016/j.jcis.2023.10.163⟩. ⟨hal-04316090⟩
Aymeric Fabien, Guillaume Lefebvre, Brice Calvignac, Pierre Legout, Elisabeth Badens, et al.. Interfacial tension of ethanol, water, and their mixtures in high pressure carbon dioxide: measurements and modeling. Journal of Colloid and Interface Science, 2022, 613, pp.847-56. ⟨10.1016/j.jcis.2022.01.058⟩. ⟨hal-03531186⟩ Plus de détails...
Hypothesis: It is particularly noteworthy to study interfacial tension behavior under pressurized carbon dioxide for supercritical processes such as crystallization or fractionation. For the latter, a liquid phase and a supercritical phase are in contact, and interfacial properties influence mass transfer phenomena and hydrodynamics. Ethanol-water mixture is a good theoretical study case also involved in a wide range of applications. Experimental: Interfacial tensions of ethanol, water and three mixtures, with an ethanol mass fraction from 0.25 to 0.75, under pressurized CO 2 were measured for pressures ranging from 0.1 MPa to 15.1 MPa at 313.15 K and 333.15 K. A specific experimental setup was used for CO 2 phase saturation. Findings: This work brings interfacial tension data of five different solutions including water and ethanol in contact with CO 2. Effects of pressure, temperature, carbon dioxide density and ethanol mass fraction are discussed regarding the literature. Significant discrepancies are found with previous literature data for ethanol-water mixtures. The "two-step" decrease observed when pressure or density increase is also discussed regarding both the concept of Widom line, and the polar and dispersive contributions of the surface tension of a component. For the first time, fair accurate interfacial tension modeling involving these contributions is addressed.
Aymeric Fabien, Guillaume Lefebvre, Brice Calvignac, Pierre Legout, Elisabeth Badens, et al.. Interfacial tension of ethanol, water, and their mixtures in high pressure carbon dioxide: measurements and modeling. Journal of Colloid and Interface Science, 2022, 613, pp.847-56. ⟨10.1016/j.jcis.2022.01.058⟩. ⟨hal-03531186⟩
