Title:	Overlimiting behavior of surface-modified heterogeneous anion-exchange membranes
Authors:	Belloň, Tomáš Slouka, Zdeněk
Citation:	BELLOŇ, T., SLOUKA, Z. Overlimiting behavior of surface-modified heterogeneous anion-exchange membranes. Journal of membrane science, 2020, roč. 610, č. SEP 1 2020. ISSN 0376-7388.
Issue Date:	2020
Publisher:	Elsevier
Document type:	článek article
URI:	2-s2.0-85085936404 http://hdl.handle.net/11025/41927
ISSN:	0376-7388
Keywords in different language:	Heterogeneous anion-exchange membrane;Electroconvection;Particle image velocimetry;Water splitting;Surface modification
Abstract in different language:	Electrochemical and electrokinetic behavior of ion-exchange systems as a result of electrostatic interactions between the fixed charge and the ionic species present in the electrolyte can significantly vary with the type of electrolyte and the membrane composition. In this paper, we studied experimentally the effect of surface modification of a heterogeneous anion-exchange membrane on its properties and overlimiting behavior. The surface modification of the anion-exchange membrane included carboxylation of its surface through benzophenone-based photochemistry followed by covalent linkage of single stranded DNA molecules. Such surface chemistry produced molecular layers of negative charge on the positively charged membrane surface. We investigated the membrane samples with different two levels of surface modification after their exposure either to KCl solutions or solutions containing a biopolymer serving as a model membrane foulant. The surface modification resulted in larger system resistances that were especially pronounced in the limiting and overlimiting region. Water splitting reaction on both the pristine and the modified membranes occurred approximately to the same extent. Unlike water splitting, electroconvection, as another mechanism driving overlimiting current, tracked by the PIV method was largely suppressed upon surface modification especially with DNA molecules. The membranes with the chemicallymodified surfaces showed smaller susceptibility towards fouling.
Rights:	Plný text není přístupný. © Elsevier
Appears in Collections:	Články / Articles OBD

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.