三种类型的商业级地石永久选择性膜的乙醇脱水性能
Leland Vane1, Franklin Alvarez1, Vasudevan Namboodiri1
1United States Environmental Protection Agency, Center for Environmental Solutions and Emergency Response, Cincinnati, OH, USA.
概括
查巴 (CHA) 和T型化物膜显示出通过蒸发进行高能效的乙醇干燥的前景. CHA膜的初始性能最高,尽管在测试的热带石膜中,长期稳定性各不相同.
科学领域:
- 膜科学和技术 膜科学和技术
- 化学工程是化学工程的组成部分.
- 材料科学是一种材料科学.
背景情况:
- 有机溶剂干燥对于重复使用至关重要,水选择性膜提供节能解决方案.
- 蒸发 (PV) 和蒸汽透 (VP) 是用于溶剂脱水的有希望的膜技术.
- 对于在溶剂干燥应用中使用商业Chabazite (CHA) 和T型热带石膜的性能数据有限.
研究的目的:
- 评估商业CHA,T型和NaA类热带石膜的性能,用于通过蒸发从乙醇中去除水.
- 在特定条件下比较这些膜的水透率和选择性.
- 在乙醇脱水过程中评估膜的长期稳定性和性能下降.
主要方法:
- 通过蒸发 (PV) 实验,使用商业级的CHA,T型和NaA化物膜进行了实验.
- 膜在50°C时测试了从乙醇中去除水分 (5重量%水分) 的情况.
- 性能指标包括水透率和永久选择性在39天内进行测量.
主要成果:
- 该CHA膜显示了最高的初始光伏水透率 (6820GPU) 和选择性 (3430).
- NaA和T型膜的初始性能较低,NaA随着时间的推移表现出显著的性能下降.
- T型膜保持了最稳定的水透率,但显示了可变的乙醇透率.
结论:
- 测试的热带石膜的光伏性能与预测一致,通常超过非热带石膜用于乙醇干燥.
- CHA和NaA膜显示出有效的乙醇脱水的潜力,尽管需要考虑长期稳定性.
- 了解依赖时间的性能变化对于设计有效的溶剂脱水系统至关重要.
相关概念视频
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Preparation of Ethers by Alcohol Dehydration
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