Modeling electrochemical transport of ions in the molten CaF2-FeO slag operating under a DC voltage

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26210%2F19%3APU136966" target="_blank" >RIV/00216305:26210/19:PU136966 - isvavai.cz</a>

Výsledek na webu

<a href="http://apps.webofknowledge.com/full_record.do?product=WOS&search_mode=GeneralSearch&qid=6&SID=E6RhdId53lWwjwLhzvN&page=1&doc=1" target="_blank" >http://apps.webofknowledge.com/full_record.do?product=WOS&search_mode=GeneralSearch&qid=6&SID=E6RhdId53lWwjwLhzvN&page=1&doc=1</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.amc.2018.01.008" target="_blank" >10.1016/j.amc.2018.01.008</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Modeling electrochemical transport of ions in the molten CaF2-FeO slag operating under a DC voltage

Popis výsledku v původním jazyce

Electrically resistive CaF2-based slags are extensively used in many metallurgical processes such as electroslag remelting (ESR). Chemical and electrochemical reactions as well as transport of ions in the molten slag (electrolyte) are critical phenomena for those processes. In this paper, an electrochemical system including two parallel, planar electrodes and a completely dissociated electrolyte operating under a DC voltage is modeled. The transport of ions by electro-migration and diffusion is modeled by solving the PoissonNernst- Planck (PNP) equations using the Finite Volume Method (FVM). The non-linear Butler-Volmer equations are implemented to describe the boundary condition for the reacting ions at the electrode-electrolyte interface. Firstly, we study a binary symmetrical electrolyte, which was previously addressed by Bazant et al. (2005), to verify the numerical model. Secondly, we employed the model to investigate our target CaF2-FeO system. The electrolyte is consisted of reacting (Fe2+) and non-reacting (Ca+2, O2-, F-) ions. Spatial distributions of concentrations of ions, charge density, and electric potential across the electrolyte at steady state are analyzed. It is found that the Faradaic reaction of the ferrous ion (Fe2+) has negligible impact on the electric potential field at very low current density (<1 A m(-2)). The strong impact of electric double layer (EDL) capacitance on the system behavior is addressed throughout our analysis. Furthermore, a linear relationship among activation (surface) overpotential and current density (<1600 A m(-2)) is observed. The simulation results helps to explain some phenomena observed in the ESR process. The higher melt rate for an anodic ESR electrode than a cathodic one is linked to the interfacial potential drop. It is found that the anodic potential drop near the anode is larger than the cathodic voltage drop near the cathode. The results are tested against an experiment. (c) 2018 Elsevier Inc. All rights rese

Název v anglickém jazyce

Modeling electrochemical transport of ions in the molten CaF2-FeO slag operating under a DC voltage

Popis výsledku anglicky

Electrically resistive CaF2-based slags are extensively used in many metallurgical processes such as electroslag remelting (ESR). Chemical and electrochemical reactions as well as transport of ions in the molten slag (electrolyte) are critical phenomena for those processes. In this paper, an electrochemical system including two parallel, planar electrodes and a completely dissociated electrolyte operating under a DC voltage is modeled. The transport of ions by electro-migration and diffusion is modeled by solving the PoissonNernst- Planck (PNP) equations using the Finite Volume Method (FVM). The non-linear Butler-Volmer equations are implemented to describe the boundary condition for the reacting ions at the electrode-electrolyte interface. Firstly, we study a binary symmetrical electrolyte, which was previously addressed by Bazant et al. (2005), to verify the numerical model. Secondly, we employed the model to investigate our target CaF2-FeO system. The electrolyte is consisted of reacting (Fe2+) and non-reacting (Ca+2, O2-, F-) ions. Spatial distributions of concentrations of ions, charge density, and electric potential across the electrolyte at steady state are analyzed. It is found that the Faradaic reaction of the ferrous ion (Fe2+) has negligible impact on the electric potential field at very low current density (<1 A m(-2)). The strong impact of electric double layer (EDL) capacitance on the system behavior is addressed throughout our analysis. Furthermore, a linear relationship among activation (surface) overpotential and current density (<1600 A m(-2)) is observed. The simulation results helps to explain some phenomena observed in the ESR process. The higher melt rate for an anodic ESR electrode than a cathodic one is linked to the interfacial potential drop. It is found that the anodic potential drop near the anode is larger than the cathodic voltage drop near the cathode. The results are tested against an experiment. (c) 2018 Elsevier Inc. All rights rese

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20303 - Thermodynamics

Projekt

—

Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2019

Kód důvěrnosti údajů

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

Název periodika

APPLIED MATHEMATICS AND COMPUTATION

ISSN

0096-3003

e-ISSN

1873-5649

Svazek periodika

357

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

17

Strana od-do

357-373

Kód UT WoS článku

000466350700026

EID výsledku v databázi Scopus

2-s2.0-85041860165