mfernandez

Thank you for your reply Brian. The paper that I'm referencing contains correlation parameters for the chemical equilibrium constants of several equations (Ai). Some of them are already in thermo_phrqpitz.dat, but a couple of them are not (deprotonation of water by ammonia, and formation of carbamate ion from ammonia and bicarbonate, both from Edwards 1978). It also includes Henry's constant parameters (Bi) and standard enthalpies of formation for NH3 and CO2 (from Rumpf 1998). The values unique to this paper are some parameters for Pitzer activity coefficients (eight binary and four ternary parameters). However I am not too familiar with the form of the equations or the data file structure, so I have no idea if this information can be integrated. Please let me know if there is anything else I can provide to offer a better description. Thanks again for your help.

Hi, I am interested in using GWB to model CO2-NH3-H2O vapor-liquid equilibria using Pitzer coefficients. Using thermo_phrqpitz.dat, this doesn't seem to be possible. Is their another data set that would allow me to do this? If not, would it be possible to edit one of the data sets in such a way to make this possible. It's worth noting that I'd like to include the carbamate ion species (e.g. H2NCOO-). There was a recent publication in the International Journal of Greenhouse Gas Control published recently (Author: Yin Xu, Title: Modeling of the NH3-CO2-H2O vapor-liquid equilibria behavior with species-group Pitzer activity coefficient model), that I though might be useful in this task. If the vapor-side modeling is not feasible, there would still be value in just modeling the closed aqueous system. If anyone has any suggestions, please let me know. Thanks!