化工学报 ›› 2025, Vol. 76 ›› Issue (11): 5951-5964.DOI: 10.11949/0438-1157.20250657

• 智能过程工程 • 上一篇    

氢气驱动电化学CO2捕集系统的过程模拟与多离子耦合传输机制

李一白1(), 刘世昌1, 王靖1,2(), 刘永忠1,2()   

  1. 1.西安交通大学化工系,陕西 西安 710049
    2.新能源系统工程与装备陕西省高校工程研究中心,陕西 西安 710049
  • 收稿日期:2025-06-18 修回日期:2025-07-21 出版日期:2025-11-25 发布日期:2025-12-19
  • 通讯作者: 王靖,刘永忠
  • 作者简介:李一白(2001—),男,硕士研究生,liyibai@stu.xjtu.edu.cn
  • 基金资助:
    国家自然科学基金重点项目(22238006);联合基金项目(U24B6016);陕西省重点研发计划项目(2025CY-YBXM-183);能源陕西实验室科技项目(ESLB202411);中国博士后基金项目(2025M771171)

Process simulations and multi-ion coupled transport mechanism for hydrogen-driven electrochemical CO2 capture system

Yibai LI1(), Shichang LIU1, Jing WANG1,2(), Yongzhong LIU1,2()   

  1. 1.Department of Chemical Engineering, Xi’an Jiaotong University, Xi’an 710049, Shaanxi, China
    2.Engineering Research Center of New Energy System Engineering and Equipment, University of Shaanxi Province, Xi’an 710049, Shaanxi, China
  • Received:2025-06-18 Revised:2025-07-21 Online:2025-11-25 Published:2025-12-19
  • Contact: Jing WANG, Yongzhong LIU

摘要:

氢气驱动的电化学CO₂捕集系统(hydrogen-driven electrochemical carbon capture system,HECCS)因低能耗和高选择性等特性受到广泛关注。HECCS中多离子耦合传输与电流密度、捕集浓度及温度等操作参数的定量关联是厘清其捕碳机制的关键。基于Maxwell-Stefan扩散方程,建立了HECCS系统捕碳过程中考虑多离子耦合传输的传质-电场耦合多物理场模型。研究表明,所建立模型可以有效地模拟HECCS系统中的多离子传输过程。通过对膜电极内pH分布、电解质电势及OH-HCO3-CO32-传输过程耦合特性的分析,厘清了不同操作参数下捕碳性能的速率限制步骤,获得了操作参数和关键控制因素对HECCS捕集通量和电子效率的影响规律。研究可为电化学CO2捕集系统的性能提升和优化设计提供理论分析和计算依据。

关键词: CO2捕集, 氢气, 离子扩散, 数学模拟, 速率限制步骤

Abstract:

Hydrogen-driven electrochemical carbon capture systems (HECCS) have been widely attracted attention due to their low energy consumption and high selectivity. Establishing a quantitative relationship between the multiple ions coupled transport mechanisms in HECCS and operating parameters such as current density, capture concentration, and temperature is the key to elucidating the underlying carbon capture mechanisms. Based on the Maxwell-Stefan diffusion equation, this paper establishes a mass transfer-electric field coupled multiphysics model for the carbon capture process in the HECCS system, taking into account multi-ion coupling transport. The results show that the proposed model can effectively simulate the multiple ions transport in the HECCS system. By analyzing the coupled behaviors of pH distribution, electrolyte potential, and the transport of OH-, HCO3- and CO32- ions within the membrane electrode assembly, the rate-limiting steps under different operating conditions are identified. The influences of various operational parameters and key controlling factors on CO2 capture flux and faradaic efficiency are determined, clarifying the mechanisms by which operating conditions affect carbon capture performance. This work provides a theoretical and computational foundation for the performance improvement and optimal design of electrochemical CO₂ capture system.

Key words: CO2 capture, hydrogen, ion diffusion, mathematical modeling, rate controlling step

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