In this study, the thermodynamics and mass transfer of CO 2 absorption in the aqueous monoethanolamine-piperazine blended solution have been studied. A correlation is proposed for the mass transfer flux of CO 2 reactive absorption.The effective parameters on the mass transfer flux are considered in both the liquid and gas phases using dimensional analysis Pi-Buckingham theorem.The effective variables were extracted as a dimensionless parameter. The dimensionless parameters are calculated from experimental data presented in the literature. The unknown constants of the mass transfer flux correlation are obtained using nonlinear regression. In the proposed correlation, the effect of operating parameters including the partial pressure, temperature, and also the dimensionless parameters of the film parameter, enhancement factor, and loading are investigated. The results showed that by increasing the loading and film parameter, the mass transfer flux was reduced. The mean absolute deviation in the proposed correlation for mass transfer flux was about 4.5%, which indicates the high accuracy of the predicted equation.