Functionalized flexible MOFs as fillers in mixed matrix membranes for highly selective separation of CO_2 from CH4 at elevated pressures

摘要

Mixed matrix membranes (MMMs) composed of a glassy polymer (polysulfone) and the flexible metal organic framework NH_2-MIL-53(A1) exhibit excellent separation properties. In contrast to most reported membranes, CO_2/CH_4 separation selectivity increases with pressure, related to the flexibility of the filler. Gas separation and purification based on membranes holds promise as energy efficient alternative to energy intensive distillation processes.1 Separation through membranes is usually based on the size and the shape of the molecules to be separated or on their interaction with the membrane material.