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 CO2 separation membranes with high gas permeability and stability performance. Firstly, the effect of MIL-101(Cr)-NH2 on the performance of EM400 was studied by preparing EM400/MIL-101(Cr)-NH2 MMMs. The addition of MIL-101(Cr)-NH2 effectively improved the mechanical properties of MMMs and increased the selectivity of CO2/N-2. Then the tripropionin (TPP) was chosen to further modify the EM400/MIL-101(Cr)-NH2 MMMs with 10 wt% MIL-101(Cr)-NH2 content by preparing EM400/MIL-101(Cr)-NH2/TPP g-MMMs. The results showed that the TPP promoted the dispersion of MIL-101(Cr)-NH2 and it greatly improved the CO2/N-2 and CO2/H-2 separation performance of the g-MMMs by increasing the FFV and the CO2 solubility coefficients at the same time. The EM400/MIL-101(Cr)-NH2/TPP gMMMs with 60 wt% TPP content had CO2 permeability of 1288.3 Barrer with the CO2 /N-2 selectivity of 22.2 and the CO2/H-2 selectivity of 7.9 at 0.1 MPa and 35 degrees C. The performance of the g-MMMs had broken the "trade-off' relationship between permeability and selectivity, and the CO2/H-2 separation performance surpassed the upper bound (2008). Meanwhile, the EM400/MIL-101(Cr)-NH2/TPP g-MMMs showed relatively good pressure resistance and great stability, which would benefit to industrial application.