Jiang, Bin Zhou, Junhan Xu, Mi Dou, Haozhen Zhang, Haiming Yang, Na Zhang, Luhong*
School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People’s Republic of China
Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin 300072, People’s Republic of China
Received 25 April 2018, Revised 21 August 2018, Accepted 31 August 2018, Available online 1 September 2018.
Membrane technology is a forward-looking approach for gas separation, while the implementation of membrane with high performance for ethylene/ethane separation still challenges the world. Herein, a multifunctional ternary deep eutectic solvent (DES)-based membrane was constructed for the cost-effective ethylene/ethane separation. The incorporation of a sweetener (Al(NO3)3) with the AgNO3/methylacetamide (NMA) mixture to form a ternary DES not only significantly promoted the ethylene/ethane selectivity but also enhanced the long-term stability of resultant membranes, which killed two birds with one stone. Various spectroscopic characterization and quantum mechanical calculations revealed that the complexing interaction between Ag+ and NMA and the complexing interaction between Al3+ and NO3− weakened the electrostatic interaction between Ag+ and NO3−, and improved the interaction energy between ethylene molecule and Ag+ carrier. By the synergy effects of two different complexing interactions, the ternary DES-based membranes exhibited high ethylene permeability, ethylene/ethane selectivity and stability, outperforming majority of the previously published data. Therefore, the membranes proved the grand potential for ethylene/ethane separation, and this work will shed light on the design of multifunctional liquid membranes for precise molecular separation.