选择性乙/乙烯分离在坚固的微孔的有机框架中
Xu Zhang1,2, Libo Li3,4, Jia-Xin Wang1
1State Key Laboratory of Silicon Materials, School of Materials Science and Engineering , Zhejiang University , Hangzhou 310027 , China.
Journal of the American Chemical Society
|December 17, 2019
概括
一种新型的与结合的有机框架 (HOF),HOF-76a,有效地将乙与乙烯分离. 这种吸附剂为生产用于工业应用的高纯度乙烯提供了有前途的解决方案.
科学领域:
- 材料科学
- 化学工程
- 吸附科学
背景情况:
- 乙 (C2H6) 和乙烯 (C2H4) 的分离对于聚合物级乙烯的生产至关重要.
- 现有的C2H6/C2H4分离方法使用与结合的有机框架 (HOF) 是有限的,因为结合相互作用较弱.
- 为选择性C2H6/C2H4分离开发强大的吸附剂仍然是一个重大挑战.
研究的目的:
- 报告一种用于选择性乙/乙烯分离的新型,超坚固的有机框架 (HOF-76a).
- 在HOF-76a中研究控制C2H6与C2H4优先结合的吸附机制.
- 展示HOF-76a在生产聚合物级乙烯中的实际应用.
主要方法:
- 新型HOF吸附剂 (HOF-76a) 的合成和表征
- 在各种压力和温度下进行气体吸附同热测量.
- 理论计算 (例如密度函数理论) 来理解吸附相互作用.
- 用于混合物吸附预测的理想吸附溶液理论 (IAST) 计算.
- 模拟和实验突破曲线分析.
主要成果:
- HOF-76a具有很高的Brunauer-Emmett-Teller (BET) 表面积 (>1100 m2/g).
- HOF-76a表明C2H6比C2H4的吸附优越,导致高度选择性的分离.
- 理论研究表明,HOF-76a的非极地表面和三角孔状结构通过更强的范德瓦尔斯相互作用有利于C2H6吸附.
- 实验突破性测试成功地从50/50C2H6/C2H4混合物中产生聚合物级乙烯.
- 获得了7.2L/kg (1.01巴) 和18.8L/kg (5.0巴) 的高生产率.
结论:
- HOF-76a是有效和选择性的C2H6/C2H4分离的基准吸附剂.
- 独特的孔隙结构和HOF-76a的表面化学是其优越的分离性能的关键.
- 这种HOF吸附剂为聚合物级乙烯的工业生产提供了可行的途径.
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