Facile Synthesis of Amine-functionalized MOFs Incorporated Polyimide MMMs with Enhanced CO2 Permselectivity

摘要

abstract_textpHere a series of amine-functionalized MOFs incorporated polyimide (PI) mixed matrix membranes (MMMs) are fabricated via an efficient method. The X-ray diffraction (XRD) and scanning electron microscope (SEM) images clearly indicate that the metal-organic framework (MOF) crystals are well-retained and dispersed into the PI matrix. In addition, the resulting MMM is continuous and compact, no defects of pinhole/cracks and agglutinated MOFs can be observed from the membrane surface. This is because the hydrogen bonding between amine-functionalized MOFs and PI can be enhanced, improving the dispersion of MOF crystals in the PI solution. More importantly, the PI/MOFs solution is further optimized by the removal of agglutinated MOFs that occur inevitably with increasing MOF loadings. The gas separation results show that the performance of MOF-incorporated MMM has been greatly improved. For instance, compared with the pure PI film, CO2 permeability can be increased by 154.4. Meanwhile, the selectivities of CO2/N-2 and CO2/CH4 are increased by 30 and 43, respectively. Pore structure and gas adsorption properties of MOFs clearly affect the performance of the resulting MMM./p/abstract_text