470212 Mmif-Based Mixed-Matrix Membranes for CO2 Separation
The molecular simulation studies in the literature revealed several possible MOF structures as outstanding candidates for MOF-based MMMs. One of these MOFs, which became prominent for CO2/CH4separation, is microporous metal–imidazolate framework (MMIF) . However, no experimental data is available in the literature to confirm the predicted performances of these MOFs, in particular no MMM studies using these MOFs are reported.
In this study, first, MMIF has been synthesized and characterized in order to experimentally verify its capability of CO2 capture. Then, it is incorporated into polyimides to prepare MMMs. Membranes are characterized with SEM, XRD, TGA, DSC and pure and mixed-gas permeability tests for CO2/CH4 and CO2/N2separations.
Contrary to simulation results and Maxwell model predictions reported in the literature, pure gas permeability measurements at 35°C and 4 bar showed that Matrimid based MMMs containing 10% MMIF improved the permeability of Matrimid by 15% and no improvement in selectivity was observed. The permeability and selectivity remained stable with an increase in MMIF loading to 20%. On the other hand, mixed gas selectivity for CO2/CH4improved significantly to 88 for 10% loading.
This work is supported by TUBITAK (Turkish Scientific and Technological Research Council) through Project No. 113M776.
- Erucar, I, Keskin, S., “Screening Metal Organic Framework-Based Mixed-Matrix Membranes for CO2/CH4 Separations”, Ind. Eng. Chem. Res., 50 (22), pp. 12606–12616 (2011).