Investigation of electrode material - Redox couple systems for reverse electrodialysis processes. Part I: Iron redox couples
- Autori: Scialdone, O.; Albanese, A.; D'Angelo, A.; Guarisco, C.; Galia, A.
- Anno di pubblicazione: 2012
- Tipologia: Articolo in rivista (Articolo in rivista)
- Parole Chiave: Electrode reaction; Electrodialysis; Iron complexes; Redox couple; Reverse electrodialysis;
- OA Link: http://hdl.handle.net/10447/82445
Abstract
The performances of electrodialysis (ED) and reverse electrodialysis (RED) processes depend on several factors, including the nature of the electrode material and of the redox couple adopted to make possible the conversion between electric power and chemical potential. In this paper, the possible utilization of iron-based redox couples (FeCl3/FeCl2, hexacyanoferrate(III)/hexacyanoferrate(II) and Fe(III)-EDTA/Fe(II)-EDTA) on graphite and DSA electrodes for RED processes was studied by a detailed experimental investigation. The hexacyanoferrate(III)/hexacyanoferrate(II) system was stable for long time (more than 12 days) in the absence of light and oxygen at high redox couple concentrations and low current densities both at compact graphite and DSA electrodes. Perfluorinated Nafion cationic membranes were found to be impermeable to the components of the redox couple. Fe(II)-EDTA exhibited a limited electrochemical stability in long term electrolyses at all adopted operative conditions, w...