A MOF-based Ultra-Strong Acetylene Nano-trap for Highly Efficient C2H2/CO2 Separation

Zheng Niu^1,*（牛政）, Xili Cui⁴, Tony Pham³, Gaurav Verma², Pui Ching Lan², Chuan Shan³, Huabin Xing⁴, Katherine A. Forrest³, Shanelle Suepaul³, Brian Space³, Ayman Nafady⁵, Abdullah M. Al-Enizi⁵, and Shengqian Ma^2,*

¹College of Chemistry, Chemical Engineering and Materials Science，Soochow University, Suzhou 215123 (P. R. China)

²Department of Chemistry, University of North Texas Denton, TX 76201 (USA)

³Department of Chemistry, University of South Florida 4202 E. Fowler Avenue, Tampa, FL 33620 (USA)

⁴Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering，Zhejiang University, Hangzhou 310027 (P. R. China)

⁵Department of Chemistry, College of Science, King Saud University，Riyadh 11451 (Saudi Arabia)

Angew. Chem. Int. Ed.2021, 60, 5283--5288

Porous materials with open metal sites have been investigated to separate various gas mixtures. However, open metal sites show the limitation in the separation of some challenging gas mixtures, such as C₂H₂/CO₂. Herein, we propose a new type of ultra‐strong C₂H₂ nano‐trap based on multiple binding interactions to efficiently capture C₂H₂ molecules and separate C₂H₂/CO₂ mixture. The ultra‐strong acetylene nano‐trap shows a benchmark Q_st of 79.1 kJ mol⁻¹ for C₂H₂, a record high pure C₂H₂ uptake of 2.54 mmol g⁻¹ at 1×10⁻² bar, and the highest C₂H₂/CO₂ selectivity (53.6), making it as a new benchmark material for the capture of C₂H₂ and the separation of C₂H₂/CO₂. The locations of C₂H₂ molecules within the MOF‐based nanotrap have been visualized by the in situ single‐crystal X‐ray diffraction studies, which also identify the multiple binding sites accountable for the strong interactions with C₂H₂. 

链接：https://onlinelibrary.wiley.com/doi/full/10.1002/anie.202016225