在催化CO2甲化过程中的测绘温度异质性与操作光发热量测量
Thimo S Jacobs1, Thomas P van Swieten2, Sander J W Vonk1,3
1Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science & Institute for Sustainable and Circular Chemistry, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
ACS nano
|October 5, 2023
概括
了解催化剂温度变化是性能的关键. 发光温度计在二氧化碳甲化过程中绘制局部温度变化图,揭示了对催化反应速率的洞察力.
科学领域:
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 精确控制反应温度对于催化剂性能评估至关重要.
- 在催化过程中测量局部温度存在重大挑战.
- 发光温度计提供远程传感,但由于对光学特性和外部因素的交叉敏感性而受到影响.
研究的目的:
- 在Ni/TiO2催化剂上的CO2甲化过程中测量微米尺度上的空间温度变化.
- 为了将这些局部温度波动与催化性能变化相关联.
- 开发和优化Y2O3:Nd3+粒子,用于精确的发光温度计.
主要方法:
- 使用的Y2O3:Nd3+颗粒与催化剂混合,用于温度依赖的发光度测量.
- 采用扫描激光激发来生成微米分辨率的温度图.
- 描述并考虑了对诸如焦炭沉积中的光吸收等参数的交叉敏感性.
主要成果:
- 引入的反应气体导致局部催化剂温度平均上升6-25K (550-640K反应堆设定温度).
- 观察到像素对像素的温度变化,标准偏差高达1.5K.
- 将这些温度变化归因于催化反应速率的局部差异.
结论:
- 微米尺度上的空间温度变化直接影响催化性能.
- 发光温度计,经过仔细的设计和表征,可以有效地绘制这些关键温度梯度.
- 了解和控制这些微尺度温度变化对于优化纳米和宏观水平的催化剂性能至关重要.
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