%0 Journal Article
%T Diffusion Study by IR Micro-Imaging of Molecular Uptake and Release on Mesoporous Zeolites of Structure Type CHA and LTA
%A Mauricio Rincon Bonilla
%A Tobias Titze
%A Franz Schmidt
%A Dirk Mehlhorn
%A Christian Chmelik
%A Rustem Valiullin
%A Suresh K. Bhatia
%A Stefan Kaskel
%A Ryong Ryoo
%A J£¿rg K£¿rger
%J Materials
%D 2013
%I MDPI AG
%R 10.3390/ma6072662
%X The presence of mesopores in the interior of microporous particles may significantly improve their transport properties. Complementing previous macroscopic transient sorption experiments and pulsed field gradient NMR self-diffusion studies with such materials, the present study is dedicated to an in-depth study of molecular uptake and release on the individual particles of mesoporous zeolitic specimens, notably with samples of the narrow-pore structure types, CHA and LTA. The investigations are focused on determining the time constants and functional dependences of uptake and release. They include a systematic variation of the architecture of the mesopores and of the guest molecules under study as well as a comparison of transient uptake with blocked and un-blocked mesopores. In addition to accelerating intracrystalline mass transfer, transport enhancement by mesopores is found to be, possibly, also caused by a reduction of transport resistances on the particle surfaces.
%K mesoporous zeolites
%K IR micro-imaging
%K diffusion
%K surface barriers
%K NaCaA
%K SAPO-34
%K paraffins
%K olefins
%U http://www.mdpi.com/1996-1944/6/7/2662