Beyond summative Effects: Synergistic enhancement in the gaseous interfacial reduction of Wüstite by the combined use of hydrogen and carbon monoxide

• Published in: Chemical engineering science 2024-10, Vol.298, p.120349, Article 120349
• Main Authors: Bai, Lingxiao, Deng, Junyi, Wang, Junlong, Zhang, Haiqing, Xu, Jian
• Format: Article
• Language: English
• Subjects: Gaseous reduction rate; Interfacial reaction; Linear programming analysis; Synergistic interactions
• ISSN: 0009-2509
• DOI: 10.1016/j.ces.2024.120349

•Synergistic interaction between H2 and CO in FeO isothermal reduction is examined.•The reduction rate in the H2-CO mixture gas is quantified via linear programming.•H2 boosts CO’s efficiency by 1.51 times when the H2-CO concentration is 30%.•Synergistic mechanisms are explained and analogized to a rabbit pulling a carrot.•A ‘waterfall’ trend depicts the enhanced rate drop with higher gas concentration. Growing environmental concerns are driving the steel industry to explore cleaner energy options, with hydrogen emerging as a promising alternative to fossil fuels. Our study investigates the interactions between hydrogen and carbon monoxide during the isothermal reduction of wüstite at 800 °C, focusing on the interfacial reaction as the rate-determining step. Using linear programming, we predict the reduction rate in the hydrogen-carbon monoxide mixture gas by quantifying each component’s contribution, validated with less than 6 % error. Hydrogen exhibits a reducing power 1.6 times that of carbon monoxide. When the total concentration of hydrogen and carbon monoxide is 30 %, an enhancement in carbon monoxide’s oxygen removal capability in ‘terrain’ regions visited by hydrogen increases the carbon monoxide utilization ratio by 1.51 times, primarily through increasing the average pore diameter to 30.28 nm. Furthermore, our study introduces the ‘waterfall’ effect, a concept derived from exploring the synergistic mechanisms between hydrogen and carbon monoxide.