The preparation and characterization of gel-mixed matrix membranes (g-MMMs) with high CO2 permeability and stability performance

The gel -mixed matrix membranes ( g -MMMs) were proposed to obtain CO 2 separation membranes with high gas permeability and stability performance. Firstly, the effect of MIL-101(Cr)–NH 2 on the performance of EM400 was studied by preparing EM400/MIL-101(Cr)–NH 2 MMMs. The addition of MIL-101(Cr)–NH 2 effectively improved the mechanical properties of MMMs and increased the selectivity of CO 2 /N 2 . Then the tripropionin (TPP) was chosen to further modify the EM400/MIL-101(Cr)–NH 2 MMMs with 10 wt% MIL-101(Cr)–NH 2 content by preparing EM400/MIL-101(Cr)–NH 2 /TPP g -MMMs. The results showed that the TPP promoted the dispersion of MIL-101(Cr)–NH 2 and it greatly improved the CO 2 /N 2 and CO 2 /H 2 separation performance of the g-MMMs by increasing the FFV and the CO 2 solubility coefficients at the same time. The EM400/MIL-101(Cr)–NH 2 /TPP g -MMMs with 60 wt% TPP content had CO 2 permeability of 1288.3 Barrer with the CO 2 /N 2 selectivity of 22.2 and the CO 2 /H 2 selectivity of 7.9 at 0.1 MPa and 35 °C. The performance of the g-MMMs had broken the “trade-off” relationship between permeability and selectivity, and the CO 2 /H 2 separation performance surpassed the upper bound (2008). Meanwhile, the EM400/MIL-101(Cr)–NH 2 /TPP g -MMMs showed relatively good pressure resistance and great stability, which would benefit to industrial application. • The TPP greatly improved the CO 2 /N 2 and CO 2 /H 2 separation performance of g -MMMs. • The g -MMMs broke the “trade-off” relationship between permeability and selectivity. • The CO 2 /H 2 separation performance of g -MMMs surpassed the upper bound (2008). • TPP increased the FFV and the CO 2 solubility coefficients of g -MMMs simultaneously. • The g -MMMs showed relatively good pressure resistance and great stability.