Selective separation of acetylene from ethylene using mixed matrix membranes with MIL-100(Fe) as a filler

Abstract

Separation of acetylene from ethylene is challenging due to the similar physicochemical properties of these two gases. In this regard, the potential of mixed matrix membranes (MMMs) has remained mostly unexplored. Herein, we synthesized MOF/polymer MMMs by incorporating an iron-based metal-organic framework (MOF), MIL-100(Fe), into Pebax polymer matrix at different filler loadings of 10, 15, and 17 wt.%. The synthesized MMMs were characterized in detail and tested for C2H2/C2H4 separation. Gas permeation measurements showed that the neat Pebax membrane has C2H2 and C2H4 permeabilities of 434.8 ± 19.0 and 29.6 ± 0.5 Barrer, respectively, at 1 bar and 35 °C, along with the corresponding C2H2/C2H4 selectivity of 14.7 ± 1. Incorporation of MIL-100(Fe) into the Pebax led to a significant improvement in C2H2 permeability and C2H2/C2H4 selectivity: The MMMs having 15 and 17 wt.% MIL-100(Fe) exhibited C2H2 permeabilities of 624.1 ± 5.4 and 509.3 ± 7.3 Barrer, respectively, corresponding to C2H2/C2H4 selectivities of 23.4 ± 2.3 and 35.6 ± 1.0. Long-term stability tests indicated that the MMMs maintained their separation performance under continuous operation for at least three days, underscoring their robustness and industrial application potential. These results set a benchmark for effectively separating C2H2 from C2H4 using the synthesized MMMs, offering valuable insights for future acetylene separation applications.