Microporous metal-organic framework with specific functional sites for efficient removal of ethane from ethane/ethylene mixtures

Publication date: Available online 17 January 2020Source: Chemical Engineering JournalAuthor(s): Ling Yang, Yong Wang, Yang Chen, Jiangfeng Yang, Xiaoqing Wang, Libo Li, Jinping LiAbstractThe separation of low concentration ethane (C2H6) from ethylene (C2H4) is of great importance in petrochemical processes; however, it is widely considered to be a challenging task. Nonetheless, utilizing suitable C2H6 selective adsorbents, adsorptive separation technology approaches can be employed to obtain high purity ethylene with high energy efficiency. Herein, we report a series of MOF materials, namely M-PNMI (M=Mn, Zn, Cd), which were synthesized using N,N'-di(4-pyridyl)-1,4,5,8-naphthalenetetracarboxdiimide. Cooperative single component adsorption analysis, as well as Ideal Adsorbed Solution Theory (IAST) calculation, and Grand Canonical Monte Carlo (GCMC) simulation revealed that these MOF materials exhibit distinctly higher adsorption capacity and preferential binding affinity for C2H6 over C2H4. These observations are due to the presence of favorable pore environments in the MOFs, which result in strong C2H6 adsorption potential. The specific C2H6 binding sites were clearly determined by density functional theory (DFT) calculations. Thus, the described M-PNMI materials can efficiently remove C2H6 from C2H6/C2H4 (1/9 and 1/15, v/v) mixtures to directly produce high purity C2H4 (>99.99 %) under ambient conditions.
Source: Chemical Engineering Journal - Category: Chemistry Source Type: research