The assessment of honeycomb structure UiO-66 and amino functionalized UiO-66 metal–organic frameworks to modify the morphology and performance of Pebax®1657-based gas separation membranes for CO2 capture applications

A new type of honeycomb structured UiO-66 metal–organic frameworks (MOF) was synthesized and amino functionalized followed by employing them to prepare mixed matrix membranes (MMM). The influences of dimethylformamide (DMF) and H 2 O/ethanol (70/30 wt.%) blend were firstly investigated on morphology, structure, and CO 2 /CH 4 separation efficiency of Pebax®1657 membranes. Based on the transmission electron microscopy (TEM) analysis, the synthesized MOF has 15 nm in diameter. DMF led to the formation of a more crystalline (based on X-ray diffraction (XRD) analysis) and more porous structure. Higher CO 2 permeability and CO 2 /CH 4 selectivity were observed as DMF was employed to fabricate neat membranes. Scanning electron microscopy (SEM) exhibited MOF agglomeration as the UiO-66 was used while the nanoparticle dispersion was enhanced when UiO-66-NH 2 was exploited. Fourier transform infrared spectroscopy (FTIR) confirmed the successful MOF incorporation into the MMMs. Ultimately, the gas separation experiments showed that CO 2 permeability was enhanced compared to the neat membrane by 44.7% and 49.4% as 10 wt.% UiO-66 and UiO-66-NH 2 were used, respectively. Moreover, the Pebax®1657-UiO-66-NH 2 MMMs exhibited 71.7% and 34.5% improvement in selectivity of CO 2 /N 2 and CO 2 /CH 4 , respectively, owing to enhancing CO 2 –OH interactions while the CO 2 /O 2 was declined by 8.8%.