在高压下,可凝结气体在性聚合物膜中的透率
Karina Schuldt1,2, Jelena Lillepärg1, Jan Pohlmann1
1Helmholtz-Zentrum Hereon, Institute of Membrane Research, Max-Planck-Str. 1, 21502 Geesthacht, Germany.
Membranes
|March 27, 2024
概括
薄膜复合膜 (TFCM) 中的气体运输显示了由于毛细血管凝结而导致的压力依赖的透峰值. 透温度不会影响气体运输,与料条件不同.
科学领域:
- 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.
- 聚合物科学 聚合物科学
背景情况:
- 薄膜复合膜 (TFCMs) 对于气体分离至关重要.
- 了解不同条件下的气体传输特性对于膜性能优化至关重要.
- 可凝结气体可以在膜选择性层中表现出复杂的行为.
研究的目的:
- 研究使用PolyActiveTM,PDMS和POMS选择性层的TFCM的气体运输特性.
- 分析温度和压力对二氧化碳和C2H6.6的膜透率的影响.
- 阐明观察到的气体运输现象的基本机制,包括透峰和温度效应.
主要方法:
- 对TFCM (PolyActiveTM,PDMS,POMS) 气体运输的实验研究.
- 系统地改变料温度 (10-34°C) 和压力 (1-65bar abs).
- 对CO2和C2H6.6的输入压力,温度和气体活动的透性依赖性的分析.
主要成果:
- 观察到CO2和C2H6的透度峰值,这取决于料压力和温度.
- PDMS和POMS表现出一致的峰值行为,而PolyActiveTM表现出更复杂的反应.
- 在所有TFCM中,透温度 (朱尔-姆森效应) 显著下降.
- 在料气活动的逐步透率下降≥1表明了运输中的料侧主导地位.
- 在胀的选择性层中的毛细血管凝结被认为是主要的机制.
结论:
- 在TFCM中,天然气运输受到输入端条件,特别是压力和温度的显著影响.
- 观察到的现象,包括透性峰值和下降,很可能是由毛细血管凝聚和透性聚类驱动的.
- 透侧温度对膜的选择性层或气体扩散的影响微不足道.
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