Thermodynamic properties for dissolution of CO2 in aqueous amine solutions

communication oraleInternational audienceCarbon Capture and Storage (CCS) is a solid option for CO 2 mitigation in the atmosphere. One option is the CO 2 capture on the industrial site of production followed by storage in secured sites. Capture processes are based on absorption/desorption cycles of selected gas in aqueous solutions of amines[1].However, these processes are energy intensive and need to be improved in order to develop an economically viable method to separate CO2 from industrial effluent. The Thermodynamic and Molecular Interaction group (CO2 capture thematic) of the Institute of Clermont-Ferrand, specializes for the last few years in the thermodynamic study of dissolution of greenhouse gases in aqueous solutions of amines [2-4]. The DACOOTA project, supported simultaneously by the French National Agency of Research (ANR) and the Natural Sciences and Engineering Research Council of Canada (NSERC), is the more recent project concerning the understanding of gas dissolution in aqueous amines for CCS. In this work, examples of absorption of CO2 in aqueous solutions of amineswill be shown at different temperatures, pressures and amine compositions. The heats of mixing of CO2 in aqueous solutions have been measured by a flow calorimetric technique [5]. The technique makes it possible simultaneous determination of the enthalpies of solution and solubility limits. A rigorous thermodynamic model of phase equilibria based on a -ϕ approach [6, 7] has also been used to predict the enthalpies of dissolutions. A comparison of the results obtained with experiments and modeling will be shown. The critical data, such as pKa versus temperature [8], needed to run the model will be highlighted, and examples of their determination willbe shown