转换度对铁基氧载体的表面动力学的影响
Victor Purnomo1, Daofeng Mei2, Ivana Staničić2
1Division of Energy and Materials, Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Göteborg 412 58, Sweden.
Energy & fuels : an American Chemical Society journal
|July 10, 2024
概括
这项研究分析了基于铁的氧气载体的化学循环,发现变化的粒径模型准确地预测了燃料转化动力学. 反应性随着温度和氧化程度的增加而增加,这对于反应器设计至关重要.
科学领域:
- 化学工程是化学工程的重要组成部分.
- 材料科学 材料科学 材料科学
- 能源转换 能源转换
背景情况:
- 氧气载体对于流化床能量转换至关重要,特别是在化学循环中.
- 了解氧载体动力学对于优化各种化学循环过程至关重要.
研究的目的:
- 在CO,H2和CH4转化过程中分析三种基于铁的氧载体 (伊尔梅尼特,铁砂,LD渣) 的表面动力学.
- 为了评估氧化程度和温度对氧载体反应性的影响.
- 评估变颗粒大小 (CGS) 模型用于预测反应动力学的适用性.
主要方法:
- 使用流化床批量反应器研究铁基氧载体和气体燃料 (CO,H2,CH4) 之间的反应.
- 研究了不同氧化度 (3-5重量%的减少) 和温度对反应动学的影响.
- 应用变化颗粒大小 (CGS) 模型以适应实验数据并确定激活能量.
主要成果:
- 变化粒径 (CGS) 模型有效地预测了以铁为基础的氧载体与气体燃料的表面动力学,即使在低氧化度.
- 碳,H2和CH4转换的激活能量分别在51-92kJ/mol,55-251kJ/mol和72-211kJ/mol之间.
- 氧载体的反应性与质量转换度和温度直接成比例,特别是在925°C以上.
结论:
- CGS模型为理解化学循环中铁基氧载体的反应动力学提供了可靠的框架.
- 温度和氧化程度显著提高了氧载体的性能,为过程优化提供了关键参数.
- 这些发现对反应工程有价值,有助于设计用于化学循环和使用氧载体的其他过程的反应器.
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