Large pore zeolitic imidazolate frameworks for hydrocarbon separation

Abstract

Metal organic frameworks (MOFs) are microporous crystalline materials with poretunability. Due to partial organic nature, MOFs are preferred fillers in fabricating themixed matrix membranes (MMMs) without interfacial voids. Among various MOFs,zeolitic imidazolate frameworks (ZIFs) have gained interest due to its stability underhumid conditions. Recently, ZIFs with extra-large pore dimensions with 12-memberedring structure have been reported. These large pores are useful in the separation ofhydrocarbons with a kinetic diameter larger than 4.5Å. In this study, energy-efficientseparation of light-to-heavy hydrocarbons will be demonstrated using large pore ZIFs.Entropic contribution for the diffusion selectivity in ZIFs are investigated thoroughly.Especially, the corresponding membrane separation performance are tested for C3 andC4 gases in the form of MMMs.