The absorption of CO2 by an aqueous mixture of N-methyldiethanolamine (MDEA)and monoethanolamine (MEA)has been investigated. A simplified and approximate mass transfer rate model based on film theory is developed and used to predict the ratc of absorption of CO2 by an aqueous solution of mixed amines. This model accounts for interaction between chemical reactions and assumes cubic concentration profiles for reactants in the film. The rates of absorption of CO2 by an aqueous MDEA/MEA system are determined in a stirred cell reactor under a wide range of conditions. The results obtained from the model are in good agreement with experimental values.