A continuous electropermutation process using ion-exchange textiles ha
s been developed in order to eliminate cations from low concentration
solutions. The applied voltage was used simultaneously as the driving
force for extracting the cations and regenerating the ion-exchange tex
tiles. Due to their sheet form and swelling in aqueous solutions, thes
e ion-exchange materials provide a good contact with ion-exchange memb
ranes. This process was tested with NaCl solutions under various exper
imental conditions; then it was applied to treate a solution containin
g metal ions such as Zn2+. The study carried out with a laboratory pil
ot developing an active membrane area of 20 cm(2) showed that the proc
ess is able to achieve high levels of removal (>95%) and to concentrat
e cations in small volumes of the receiving compartment. The presence
of ion-exchange textiles in the feed compartment of the ED stack allow
s a lower power consumption than with conventional electrodialysis.