Intracrystalline Diffusion in Mesoporous Zeolites

摘要: Specially synthesized extra-large crystallites of zeolite LTA with intentionally added mesoporosity are used for an in-depth study guest diffusion in hierarchical nanoporous materials by the pulsed field gradient NMR technique. Using propane as a molecule, intracrystalline mass transfer is demonstrated to be adequately described single effective diffusivity resulting from weighted average diffusivities two (micro- and meso-) pore spaces. Gas-kinetic order-of-magnitude estimates satisfactory agreement experimental data thus shown provide straightforward means predicting quantifying benefit hierarchically structured comparison their purely microporous equivalent.