N. Pismenskaya et al., Transport of weak-electrolyte anions through anion exchange membranes - Current-voltage characteristics, J MEMBR SCI, 189(1), 2001, pp. 129-140
Transport of salts of phosphoric and carbonic acids through anion exchange
membranes (AEM) is studied by means of current-voltage responses. Concentra
tion polarisation of such membrane systems is accompanied by a change in th
e electrolyte concentration at the membrane-solution interface due to hydro
lysis reactions. Current-voltage characteristics (CVC) on HPO42- or PO43- i
on-containing systems with modified AEM selectively permeable to mono-charg
ed anions present two waves like in electrode multi-component systems with
multi-stage electrochemical reactions. This phenomenon does not occur with
nonmodified AEMs, It is also the case with all the AEMs studied for solutio
ns containing HCO3- or CO32- salts because of close values of electrical re
sistances of the membranes in these both ionic forms. (C) 2001 Elsevier Sci
ence B.V. All rights reserved.