The diploma thesis is focused on the thermodynamic characterization of an aqueous 3-amino-1-propanol (AP) solution, which is used as a promising solvent for post-combustion CO2 capture from exhaust gases. The theoretical part contains a description of the solvent properties and the thermodynamic model selected for representation of the CO2 behavior in the solvent blend. The main task of this work was divided in two optimization sections. The first section was devoted to modeling of the vapor–liquid equilibrium (VLE) of the binary AP-water system using the NRTL activity coefficient framework. In the second section, the model was extended by the electrolyte NRTL framework including CO2 for a complete description of phase equilibrium in the ternary AP-H2O-CO2 system. Model elaboration and calculations were done in the MATLAB programming language. A literature review of all available VLE data was performed and the collected data were used to regress the interaction parameters of the NRTL model. For the full description of the ternary system, the phase equilibrium was coupled with the chemical reactions in the liquid phase. Representation of the simulation results showed a very good agreement with the experimental data and a reasonable description of the CO2 solubility in the selected alkanolamine solution. The developed model was further used to describe the liquid phase speciation and heat of absorption evaluation that is directly related to the energy requirements of the chemical absorption process. Regressed interaction parameters and chemical equilibrium constants in this work can be used in the design and simulation of the process.