In this study, mathematical modeling of CO 2 reactive absorption by monoethanolamine solution in spray and packed column has been investigated. Considering liquid film formation and effect of it on gas phase mass transfer coefficient and absorption efficiency is one of the novelty aspects of this study. Ignoring liquid film formation causes error 10%. A tuning coefficient for gas phase mass transfer in no film modeling with 80% of experimental data using Genetic Algorithm was achieved. Inter tuning coefficient in no film modeling causes modeling results be closer to experimental data with determination coefficient 0.89 and film modeling results with determination coefficient 0.93. Also temperature effects and droplet diameter changing was considered that are another novelty aspects in this study. Effect of some parameters like gas flow rate, liquid flow rate, liquid to gas flow ratio, monoethanolamine concentration in liquid phase and CO 2 concentration in gas phase on absorprion efficiency have been investigated. Results of this modeling show that gas phase mass transfer coefficient in spray column is 2-7 more than packed column. In final, using Genetic Algorithm, some operation conditions have been optimized. Maximum absorption efficiency for spray and packed column were 100% and 86% resoectively. Keywords: CO 2 , spray column, packed column, monoethanolamine, reactive absorption, genetic algorithm
