Measurement of Oxygen Potential in Molten Oxides and Its Application to Viscosity Studies

Youngjae Kim; Dongju Shin

doi:10.7844/kirr.2025.34.4.64

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2025 Vol.34, Issue 4 Preview Page

Research Paper

Measurement of Oxygen Potential in Molten Oxides and Its Application to Viscosity Studies 용융 산화물의 산소 포텐셜 측정과 점성 연구에의 활용

31 August 2025. pp. 64-70

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Abstract

In high-temperature pyrometallurgical and glass production processes, the oxygen potential of molten oxides is critical for controlling the quality and properties of metal and glass. Especially in molten oxides containing transition metals, oxygen potential determines the distribution of their oxidation states, which significantly impacts key material properties such as viscosity, electrical characteristics, and optical absorption of the melt. This study utilized oxygen sensor to measure the oxygen potential of molten oxides in a TiO₂ slag process, analyzing the changes in oxygen potential with the addition of B₂O₃ flux. Based on the oxygen potential data obtained through electromotive force (EMF) measurements, the activities of transition metal (Fe, Ti) oxides were thermodynamically calculated. Experimental results confirmed that the oxygen potential of the molten oxide changed with B₂O₃ addition, consequently affecting the activities of FeO, TiO₂, and Ti₂O₃. Furthermore, the correlation between the activity changes of individual oxides due to oxygen potential variations and the structural changes in the molten oxide system was investigated. This confirms the critical importance of oxygen potential measurement and the analysis of transition metal oxidation activities for understanding the thermophysical properties of molten oxide systems containing transition metals.

Keywords

TiO₂ slag process

oxygen potential

activity

molten oxide

고온 건식 제련 및 유리 생산 공정에서 용융 산화물의 산소 포텐셜은 금속 및 유리의 품질과 물성을 제어하는 데 매우 중요하다. 특히 전이 금속을 포함하는 용융 산화물에서는 산소 포텐셜이 이들 원소의 산화 상태를 결정하며, 이는 용융물의 점도, 전기적 특성, 광학적 흡수 등 핵심 물성에 큰 영향을 미친다. 본 연구에서는 TiO₂ 슬래그 공정에서 산소 센서 기술을 활용하여 용융 산화물의 산소 포텐셜을 측정하고, B₂O₃ 플럭스 첨가에 따른 산소 포텐셜 변화를 분석하였다. 기전력(EMF) 측정을 통해 얻은 산소 포텐셜 데이터를 기반으로 전이 금속(Fe, Ti) 산화물의 활동도를 열역학적으로 계산하였다. 실험 결과, B₂O₃ 첨가에 따라 용융 산화물의 산소 포텐셜이 변화하며, 이로 인해 FeO, TiO₂, Ti₂O₃ 등의 활동도가 영향을 받는 것을 확인하였다. 또한 산소 포텐셜 변화에 따른 각 산화물들의 활동도 변화와 용융 산화물계의 구조 변화와의 상관 관계를 고찰하였다. 이를 통하여 전이 금속을 포함하는 용융 산화물계의 열물성을 이해하는 데 있어 산소 포텐셜 측정과 전이 금속의 활동도 분석이 매우 중요함을 확인하였다.

키워드

TiO₂ 슬래그 공정

산소 포텐셜

활동도

용융 산화물

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Information

Publisher :The Korean Institute of Resources Recycling
Publisher(Ko) :한국자원리싸이클링학회
Journal Title :Resources Recycling
Journal Title(Ko) :자원리싸이클링
Volume : 34
No :4
Pages :64-70
Received Date : 2025-08-04
Revised Date : 2025-08-20
Accepted Date : 2025-08-21
DOI :https://doi.org/10.7844/kirr.2025.34.4.64

Resources Recycling ISSN:2765-3439(Print) 2765-3447(Online) 자원리싸이클링

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