首页|Self-diffusion of mixed xylene isomers in ZIF-71 crystals dispersed in a polymer to form a hybrid membrane
Self-diffusion of mixed xylene isomers in ZIF-71 crystals dispersed in a polymer to form a hybrid membrane
扫码查看
点击上方二维码区域，可以放大扫码查看
原文链接
NSTL
~(13)C pulsed field gradient(PFG)NMR was used to quantify self-diffusion of a p-xylene/o-xylene mixture inside zeolitic imidazolate framework-71(ZIF-71)crystals dispersed in a Torlon polymer to form a ZIF-71/Torlon mixed-matrix membrane(MMM).The corresponding reference PFG NMR measurements with a bed of a loosely packed bed of ZIF-71 crystals were also performed.This study is motivated by a demonstrated potential of ZIF-based MMMs for liquid separations.Selective ~(13)C isotopic labelling of each xylene isomer was used to ensure that the self-diffusivity of each isomer in the mixture is measured independently and correctly.The diffusion measurements were performed at different diffusion times at 296 K.The observed dependencies of intra-ZIF self-diffusivities in ZIF-71/Torlon MMMs and the corresponding ZIF-71 crystal beds on diffusion time were explained by an influence of the external crystal surface on the studied diffusion process.Analysis of the time dependencies of the self-diffusivities measured for each xylene isomer allowed obtaining intra-ZIF self-diffusivities not perturbed by crystal surface effects as well as the corresponding diffusion selectivity for the studied sorbate mixture.The reported selectivity of around 4 demonstrates promising separation behavior of the considered membrane type.
NSTL
