Molecular sieving of tetraalkylammonium cations on cation exchange systems in DC electric field

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22340%2F20%3A43921530" target="_blank" >RIV/60461373:22340/20:43921530 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/49777513:23640/20:43959000

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S1383586619347586?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S1383586619347586?via%3Dihub</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.seppur.2020.116691" target="_blank" >10.1016/j.seppur.2020.116691</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Molecular sieving of tetraalkylammonium cations on cation exchange systems in DC electric field

Popis výsledku v původním jazyce

Ion exchange membranes and ion exchange resin particles are widely used in electro-membrane separation processes such as electrodeionization and electrodialysis. The internal structure of these ion exchange systems implicitly determines their properties, which, in turn, strongly affect the efficiency of the separation process. Here, we indirectly investigate the internal structure of a heterogeneous cation exchange membrane and cation exchange resin particles with the use of homologous series of tetraalkylammonium chlorides. The tetraalkylammonium cations form a series of cations of various sizes amendable for sieving on the studied systems. This series is used for determination of the cation of critical size. The performed experimental study focuses on investigating characteristic features of current-voltage curves measured for individual tetraalkylammonium chloride solutions and their effect on water splitting reaction and electroconvection. Our experimental data show that while tetramethyl-, tetraethyl-, and tetrapropylammonium cations can easily be exchanged by both the membranes and the resin particles, tetrapentyl- and tetrahexylammonium cations are poorly exchanged by both studied systems due to their size. Tetrabutylammonium cation, possessing the Stokes diameter of around 1 nm, turns out to be the cation with the critical size. We observe a strong effect of the counterion size on the occurrence of electroconvection that is pertinent to the overlimiting region of the ion exchange systems. While small counterions allow intensive electroconvection to develop, large counterions have a damping effect on the electroconvective motion. The measurement of the pH changes in our systems during chronoamperometric experiments indicates that water splitting takes place in none of them. Our results classify counterions into two groups based on their ability to pass through the investigated cation exchange systems. The first group includes counterions easily exchanged by the ion exchange system. The other group contains cations that cannot be exchanged due to their size. The counterions from the second group are possible foulants with increased potential for adsorption onto the cation exchange systems due to strong electrostatic attractions. Our technique can be used for the determination of critical sizes of other cation exchange systems. © 2020 Elsevier B.V.

Název v anglickém jazyce

Molecular sieving of tetraalkylammonium cations on cation exchange systems in DC electric field

Popis výsledku anglicky

Ion exchange membranes and ion exchange resin particles are widely used in electro-membrane separation processes such as electrodeionization and electrodialysis. The internal structure of these ion exchange systems implicitly determines their properties, which, in turn, strongly affect the efficiency of the separation process. Here, we indirectly investigate the internal structure of a heterogeneous cation exchange membrane and cation exchange resin particles with the use of homologous series of tetraalkylammonium chlorides. The tetraalkylammonium cations form a series of cations of various sizes amendable for sieving on the studied systems. This series is used for determination of the cation of critical size. The performed experimental study focuses on investigating characteristic features of current-voltage curves measured for individual tetraalkylammonium chloride solutions and their effect on water splitting reaction and electroconvection. Our experimental data show that while tetramethyl-, tetraethyl-, and tetrapropylammonium cations can easily be exchanged by both the membranes and the resin particles, tetrapentyl- and tetrahexylammonium cations are poorly exchanged by both studied systems due to their size. Tetrabutylammonium cation, possessing the Stokes diameter of around 1 nm, turns out to be the cation with the critical size. We observe a strong effect of the counterion size on the occurrence of electroconvection that is pertinent to the overlimiting region of the ion exchange systems. While small counterions allow intensive electroconvection to develop, large counterions have a damping effect on the electroconvective motion. The measurement of the pH changes in our systems during chronoamperometric experiments indicates that water splitting takes place in none of them. Our results classify counterions into two groups based on their ability to pass through the investigated cation exchange systems. The first group includes counterions easily exchanged by the ion exchange system. The other group contains cations that cannot be exchanged due to their size. The counterions from the second group are possible foulants with increased potential for adsorption onto the cation exchange systems due to strong electrostatic attractions. Our technique can be used for the determination of critical sizes of other cation exchange systems. © 2020 Elsevier B.V.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20401 - Chemical engineering (plants, products)

Projekt

<a href="/cs/project/GA18-13491S" target="_blank" >GA18-13491S: Interakce nabitých polymerů s heterogenními iontově-výměnnými membránami</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2020

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Separation and Purification technology

ISSN

1383-5866

e-ISSN

—

Svazek periodika

241

Číslo periodika v rámci svazku

JUN 15 2020

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

9

Strana od-do

—

Kód UT WoS článku

000527318800054

EID výsledku v databázi Scopus

2-s2.0-85079606756