Abstract
An extension of the Debye-Hückel model was used to re-evaluate the MDEA protonation constant as a function of temperature and ionic strength. The Debye-Hückel limiting slope was estimated and the suggested parameters are successfully representing the data. The ionic strength was calculated by the speciation generated in the system and not only from the salt background concentration. Correlations for the protonation constant of MDEA were proposed for infinite dilution and high ionic strength and the standard thermodynamic properties for protonated MDEA were calculated.