化工学报 ›› 2025, Vol. 76 ›› Issue (7): 3286-3294.DOI: 10.11949/0438-1157.20241408

• 催化、动力学与反应器 • 上一篇    下一篇

化学链制氢系统中磁铁矿氧载体的CO还原特性研究

卢煦旸(), 徐强(), 康浩鹏, 史健, 曹泽水, 郭烈锦()   

  1. 西安交通大学动力工程多相流国家重点实验室,陕西 西安 710049
  • 收稿日期:2024-12-04 修回日期:2025-04-10 出版日期:2025-07-25 发布日期:2025-08-13
  • 通讯作者: 徐强,郭烈锦
  • 作者简介:卢煦旸(1996—),男,博士研究生,luxjtu@163.com
  • 基金资助:
    国家重点研发计划项目(2023YFB4204000);国家自然科学基金项目(52488201)

The CO reduction characteristics of magnetite oxygen carriers in chemical looping hydrogen production systems

Xuyang LU(), Qiang XU(), Haopeng KANG, Jian SHI, Zeshui CAO, Liejin GUO()   

  1. State Key Laboratory of Multiphase Flow in Power Engineering, Xi’an Jiaotong University, Xi’an 710049, Shaanxi, China
  • Received:2024-12-04 Revised:2025-04-10 Online:2025-07-25 Published:2025-08-13
  • Contact: Qiang XU, Liejin GUO

摘要:

磁铁矿作为化学链制氢系统的氧载体,具有低成本和环境友好的显著优势。然而,其在CO还原过程中的反应速率受控机制仍不完全明晰。采用热重分析方法探讨了650~900℃条件下20%CO等温还原磁铁矿的反应特征和多步反应动力学。XRD半定量分析结果表明,Fe3O4→FeO和FeO→Fe两步反应的耦合关系是温度依赖的。在650~750℃温度区间,两步反应高度重叠;在800~900℃温度区间,两步反应串联发生。在此基础上采用基于JMA模型的方法进行动力学分析,第一步反应受化学反应模型或三维成核模型(Avrami-Erofe’ev模型)控制,第二步反应则受扩散模型控制。

关键词: 化学链, 一氧化碳, 化学分析, 还原, 动力学模型

Abstract:

Magnetite has the significant advantages of low cost and environmental friendliness as an oxygen carrier in chemical looping hydrogen production system. However, the controlled mechanisms of its reaction rate during CO reduction remain are not fully understood. In this study, thermogravimetric analysis was used to investigate the reaction characteristics and multi-step reaction kinetics of 20%CO isothermal reduction of magnetite under conditions ranging from 650℃ to 900℃. The semi-quantitative analysis results indicate that the coupling relationship between the two-step reactions Fe₃O₄→FeO and FeO→Fe is temperature-dependent. In the temperature range of 650—750℃, the two-step reactions are highly overlapped, whereas in the temperature range of 800—900℃, the two steps occur in a sequential manner. Based on this, kinetic analysis was performed using the JMA model approach. The first step reaction is controlled by the chemical reaction model or three-dimensional nucleation model (Avrami-Erofe’ev model), while the second step reaction is controlled by the diffusion model.

Key words: chemical looping, carbon monoxide, chemical analysis, reduction, kinetic modeling

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