Mass transfer limitation phenomena across the separator in a zero-gap alkaline water electrolysis stack: Anion-selective polymer electrolyte membrane vs. Zirfon™ Perl UTP 500 case study

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22310%2F24%3A43927763" target="_blank" >RIV/60461373:22310/24:43927763 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S1385894723060850?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S1385894723060850?via%3Dihub</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.cej.2023.147354" target="_blank" >10.1016/j.cej.2023.147354</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Mass transfer limitation phenomena across the separator in a zero-gap alkaline water electrolysis stack: Anion-selective polymer electrolyte membrane vs. Zirfon™ Perl UTP 500 case study

Popis výsledku v původním jazyce

Endeavours to decrease the KOH concentration in a circulating medium represent an important target of today&apos;s research. They are connected with current efforts to increase the flexibility of alkaline water electrolysis and improve its efficiency with regard to renewable energy sources. This study reports on the impact of reduced KOH solution concentration on mass and charge transport in a laboratory alkaline water electrolysis stack with two separator types. The separators used are a homogeneous anion-selective polymer-electrolyte membrane based on chloromethylated polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene copolymer functionalised by 1,4–diazabicyclo[2.2.2]octane and a commercial composite porous Zirfon™ Perl UTP 500 diaphragm. The stack was assembled in zero-gap mode and a bipolar connection of the electrodes was used. Load curves were recorded for different KOH concentrations and operational temperatures to assess the performance of the stack. Surprisingly, mass transfer limiting behaviour of the stack was observed at KOH concentrations below 2 wt% KOH for the Zirfon™ Perl UTP 500 separator. This was not the case for the stack utilising an anion-selective membrane as a separator. A 1-dimensional, single cell, stationary mathematical model was developed and implemented to clarify this phenomenon and to understand the details of the mass transport across the different types of separators in this process. This information is crucial for understanding obstacles faced once the concentration of KOH approaches zero, i.e., the final target of research in this field. © 2023 The Author(s)

Název v anglickém jazyce

Mass transfer limitation phenomena across the separator in a zero-gap alkaline water electrolysis stack: Anion-selective polymer electrolyte membrane vs. Zirfon™ Perl UTP 500 case study

Popis výsledku anglicky

Endeavours to decrease the KOH concentration in a circulating medium represent an important target of today&apos;s research. They are connected with current efforts to increase the flexibility of alkaline water electrolysis and improve its efficiency with regard to renewable energy sources. This study reports on the impact of reduced KOH solution concentration on mass and charge transport in a laboratory alkaline water electrolysis stack with two separator types. The separators used are a homogeneous anion-selective polymer-electrolyte membrane based on chloromethylated polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene copolymer functionalised by 1,4–diazabicyclo[2.2.2]octane and a commercial composite porous Zirfon™ Perl UTP 500 diaphragm. The stack was assembled in zero-gap mode and a bipolar connection of the electrodes was used. Load curves were recorded for different KOH concentrations and operational temperatures to assess the performance of the stack. Surprisingly, mass transfer limiting behaviour of the stack was observed at KOH concentrations below 2 wt% KOH for the Zirfon™ Perl UTP 500 separator. This was not the case for the stack utilising an anion-selective membrane as a separator. A 1-dimensional, single cell, stationary mathematical model was developed and implemented to clarify this phenomenon and to understand the details of the mass transport across the different types of separators in this process. This information is crucial for understanding obstacles faced once the concentration of KOH approaches zero, i.e., the final target of research in this field. © 2023 The Author(s)

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10405 - Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)

Projekt

<a href="/cs/project/EF16_025%2F0007414" target="_blank" >EF16_025/0007414: Palivové články s nízkým obsahem platinových kovů</a><br>

Návaznosti

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

Rok uplatnění

2024

Kód důvěrnosti údajů

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

Název periodika

Chemical Engineering Journal

ISSN

1385-8947

e-ISSN

1873-3212

Svazek periodika

479

Číslo periodika v rámci svazku

Volume 479

Stát vydavatele periodika

CH - Švýcarská konfederace

Počet stran výsledku

17

Strana od-do

—

Kód UT WoS článku

001136185000001

EID výsledku v databázi Scopus

2-s2.0-85180419354