After a short introduction of the expertise of her research group, Membrane Materials and Processes at Eindhoven University of Technology, Professor Kitty Nijmeijer will discuss the recent work on the permeation behaviour of water vapour from supercritical carbon dioxide (scCO2).
scCO2 is frequently used in the food industry to extract water from food. Once saturated with water, the scCO2 needs to be regenerated to be reused. A promising way to do so is by using water vapour permeable membranes. To minimize CO2 losses, especially low CO2 permeabilities are essential.
Although much is known about gas permeation as function of temperature and pressure, only very limited data under supercritical conditions are available, although this determines the ultimate process configuration and associated economics. To address this, we experimentally investigated the CO2 permeability of three types of dense membranes, Nafion®, natural rubber and PDMS at a range of pressures (up to 195 bar) and temperatures (up to 55 °C) mostly focusing on supercritical conditions.
At lower pressures, permeation follows the behavior described in literature. However, at the transition to supercritical conditions and above, a completely different, unexpected behavior that has large implications for the final process is observed and will be explored in this talk.