The results of the experimental and theoretical investigations on the occurrence of cellular convection during chemisorption in packed columns are presented. Experiments in the systems CO2-aqueous solutions of MEA and CO2-aqueous solutions of DEA proved that cellular convection indeed occurs during chemisorption in packed columns and that it can significantly increase the mass transfer rate. The qualitative analysis of the phenomenon is carried out. The influence of certain parameters characterizing mass transfer (the mass transfer coefficient in the liquid phase, initial concentrations of reactants) on the intensity of cellular convection has been analysed. Theoretical considerations confirm the possibility of the occurrence of cellular convection in the systems under investigation.