Synthesis of MIL-88B(Fe)/Matrimid mixed-matrix membranes with high hydrogen permselectivity

A cheap and biocompatible metal-organic framework MIL-88B(Fe) (MIL = Material Institut Lavoisier) was synthesized and incorporated into Matrimid (R) 5218 to fabricate mixed-matrix membranes (MMMs) for gas separation. Separation performances of the MIL-88B(Fe)/Matrimid MMMs were tested for the single gas permeation of H-2 and CH4 as well as the mixture gas separation of an equimolar binary H-2-CH4 mixture. Due to the molecular sieving effect, the incorporation of MIL-88B(Fe) can enhance H-2 permeability but hinder the transport of CH4 in MIL-88B(Fe)/Matrimid MMMs, thus resulting in enhanced separation selectivity of H-2-CH4. At 298 K and Delta P = 3.0 bar, compared with those of a pure polymeric membrane, the H-2 permeability and H-2-CH4 mixture separation factor of MMMs with a MIL-88B(Fe) loading of 10% increased by 16% and 66%, respectively. In addition, the operation temperature has a significantly positive effect on the separation of a H-2-CH4 mixture.