Influence of Filler Pore Structure and Polymer on the Performance of MOF‐Based Mixed‐Matrix Membranes for CO₂ Capture

Abstract

To gain insight into the influence of metal-organic framework (MOF) fillers and polymers on membrane performance, eight different composites were studied by combining four MOFs and two polymers. MOF materials (NH -MIL-53(Al), MIL-69(Al), MIL-96(Al) and ZIF-94) with various chemical functionalities, topologies, and dimensionalities of porosity were employed as fillers, and two typical polymers with different permeability-selectivity properties (6FDA-DAM and Pebax) were selected as matrices. The best-performing MOF-polymer composites were prepared by loading 25 wt % of MIL-96(Al) as filler, which improved the permeability and selectivity of 6FDA-DAM to 32 and 10 %, while for Pebax they were enhanced to 25 and 18 %, respectively. The observed differences in membrane performance in the separation of CO from N are explained on the basis of gas solubility, diffusivity properties, and compatibility between the filler and polymer phases.

Towards High Performance Metal–Organic Framework–Microporous Polymer Mixed Matrix Membranes: Addressing Compatibility and Limiting Aging by Polymer Doping

“…As‐prepared NH 2 ‐MIL‐53 crystals show a diffraction pattern coherent with the np framework configuration, but diffractions ascribed to the lp MOF structure emerge in the pattern of the cast PIMAT membrane. The intensity ratio of the lp / np reflections in the NH 2 ‐MIL‐53(Al)/PIMAT is higher than NH 2 ‐MIL‐53(Al)/PIM‐1 membrane, suggesting, as previously reported by our group (Matrimid in this case), the partial penetration of Matrimid into the MOF pores (Figure b).…”

An insight into the effect of azobenzene functionalities studied in UiO-66 frameworks for low energy CO2 capture and CO2/N2 membrane separation

“…S21 and S22 and detailed calculation is given in Table S3 in the ESI †). 50 The result is then presented in Fig. 5(C).…”

Covalent and Selective Grafting of Polyethylene Glycol Brushes at the Surface of ZIF-8 for the Processing of Membranes for Pervaporation

“…However, whatever the targeted domain of application (biomedicine, separation…), the MOFs/polymer composites suffer from several limitations mainly related to a low compatibility between MOFs and polymers. [13][14][15][16] To cope with these problems, an efficient surface modification of MOFs is required. In general, the most desirable surface modification of MOFs NPs is a selective covalent grafting of a thin organic or polymeric layer at their external surface with a good control of the surface density of functional groups while preserving the crystalline structure and the porosity of the MOF.…”