The present paper tries to characterize the gas/liquid mass transfer processes in relation to the absorbent phase, employing binary mixtures of normal alkanes as liquid phase. The absorbent phase was in each case, had different binary relations between dodecane + heptane and dodecane + octane. Firstly, the absorption process in pure liquid phase was evaluated and characterized as regards to the operational variables. The effects produced by the mixture composition and the stirring rate upon the mass transfer process were also studied, in relation to the use of binary mixtures as liquid phases. (c) 2005 Elsevier B.V. All rights reserved.