一条了解乙-乙烯混合物中石化伊米达酸框架-8的乙吸附选择性的途径
Jaquebet Vargas-Bustamante1, Roberto Salcedo1, Jorge Balmaseda1
1Departamento de Polímeros, Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Ciudad Universitaria, Coyoacán, Ciudad de México 04510, Mexico.
Materials (Basel, Switzerland)
|October 14, 2023
概括
这项研究表明,ZIF-8可以选择性地吸附乙而不是乙烯,这对于减少乙烯生产造成的污染至关重要. 乙与ZIF-8形成键,解释了它在高温下更高的亲和力.
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.
- 环境科学 环境科学
背景情况:
- 乙烯生产对环境的影响需要节能的分离方法.
- 使用像ZIF-8这样的分子的乙和乙烯的吸附分离是一种有希望的替代方案.
- 在更高的温度下,ZIF-8的乙选择性和吸附行为仍然不太清楚.
研究的目的:
- 在低压和高温下研究ZIF-8上乙和乙烯的吸附.
- 阐明ZIF-8对乙的选择性的潜在机制.
- 为设计改进的吸附分离系统提供基础.
主要方法:
- 使用零长度列色谱在311 K,333 K和363 K处测试吸附异温的实验测量.
- 密度函数理论 (DFT) 和量子力学建模用于原子层相互作用分析.
- 理想吸附溶液理论 (IAST) 用于估计选择性.
主要成果:
- ZIF-8对乙比乙烯具有选择性,随着压力增加,选择性从2.8降至2.0.
- 乙的吸附度保持不变 (~-10kJ/mol),而乙烯的吸附度则随着温度的增加而下降.
- 据DFT计算,乙与ZIF-8形成键,与乙烯不同.
结论:
- 乙在ZIF-8上的优先吸附归因于结相互作用.
- 在分子水平上理解这些相互作用是优化吸附性分离过程的关键.
- 这项研究为开发可持续技术提供了基础,以减轻乙烯生产对环境的影响.
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