通过热重力测量吸附脱落进行BET和凯尔文分析
Kurt W Stahlfeld1, Erica L Belmont1
1Department of Mechanical Engineering, The University of Wyoming, Laramie, Wyoming 82071, United States.
Langmuir : the ACS journal of surfaces and colloids
|June 9, 2023
概括
一种新的热重力测量脱吸技术为透材料的特征提供了冷物理吸收的替代方案. 该方法使用易于获得的吸附剂准确确定表面积和毛孔大小分布.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
背景情况:
- 具有纳米尺寸毛孔的多孔固体对于过,电池,催化和碳封存等应用至关重要.
- 目前的表征依赖于冷物理吸收 (例如,布鲁纳uer-Emmett-Teller分析),它在预测吸附物相互作用方面存在局限性,并提出了实验挑战.
- 对于多孔材料而言,显然需要使用替代的,更具多功能性的特征化方法.
研究的目的:
- 介绍一种热重力测量溶解技术,用于确定多孔固体的表面积和孔径分布.
- 通过将结果与传统的冷物理吸收技术进行比较来验证这种方法.
- 扩大多孔材料表征的适用范围,超越了冷吸附剂.
主要方法:
- 使用热重力测量分析仪 (TGA) 来测量温度依赖的吸附物质量损失.
- 从TGA数据中导出吸附等温体.
- 应用于多层系统的布鲁纳uer-Emmett-Teller (BET) 理论和非多层系统的凯尔文方程,以确定表面积和孔径分布.
主要成果:
- 成功地将热重力测量溶解方法应用于四种吸附剂,使用水和烯作为吸附剂.
- 获得的表面积和孔径分布数据与冷物理吸收的数据相比较.
- 证明了该方法对于温度高于环境温度的沸点的吸附剂的可行性.
结论:
- 热重力测量脱吸是一种可行的,可能更具多功能性的替代品,用于对多孔材料进行特征化的冷物理吸收.
- 这种技术克服了冷方法的一些局限性,提供了更广泛的应用.
- 该研究验证了TGA的使用,以确定主要的多孔材料特性.
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