The facilitated extraction of the EDA and EDAH+ through the homogeneous membrane Nafion 324 and the heterogeneous membrane Rhone Poulenc CRP have been studied. The transport fluxes obtained by facilitated extraction of EDA or EDAH+ are the highest with the homogeneous membrane Nafion 324. In order to define the optimum conditions of extraction, we have determined the apparent stability coefficient relative to the protonation equilibria involving H+, EDAH+ and 14EDAH22+"> ion exchangers. The protonation reaction performed with the cation-exchange membrane Nafion 324 demonstrates a higher affinity for the divalent ions than for monovalent ions.