Basic Alkylamine Functionalized PAF‐1 Hybrid Membrane with High Compatibility for Superior CO2 Separation from Flue Gas

Abstract

AbstractFunctionalized porous aromatic frameworks (PAFs) are excellent candidate materials for hybrid membrane fabrication. However, tailoring PAFs for membrane CO2 separation with desirable performance is still a challenge. Here, facile fabrication of functional hybrid alkylamine‐modified PAF‐1 containing membranes with high compatibility for efficient CO2/N2 separation is reported. The methylamino groups are installed on PAF‐1 resulting in PAF‐1‐CH2NH2 that has a high surface area of over 1400 m2 g–1 and unique CO2 adsorption with CO2/N2 thermodynamic selectivity of over 1000. Amidation reaction is developed for PAF‐1‐CH2NH2 cross linking with cPIM‐1 (carboxylic polymer of intrinsic microporosity), giving a homogenous compatible membrane of PAF‐1‐CH2NH2—cPIM‐1 with outstanding CO2 permeability (≈10790 Barrer) and high CO2/N2 permselectivity (≈43). This membrane outperforms the counterparts derived from parent PAF‐1 and phenylamine PAF‐1 and possesses superior performance to other relevant membranes for CO2/N2 separation. Such a membrane can selectively and stably separate CO2 from N2 in a simulated flue gas mixture, demonstrating its huge potential in carbon capture.