Zeolite Mixed Matrix Membranes Research Articles

Preparation and properties of superglassy polymers — zeolite mixed matrix membranes

Inorganic fillers usually depress the perme-ability of most polymers, whereas the opposite isobserved for the so-called superglassy polymers,characterized by very high free volume and per-meability. The higher permeability obtained bydispersing fine particles of hydrophobic silica inPTMSP, PMP and Teflon AF membranes is prof-itable for different purposes [1]. In this work,zeolites of different size have been modified andincluded in Teflon AF 1600. The transport prop-erties of the resulting dense, defect-free mixedmatrix membranes have been determined by gaspermeation experiments.

Enhanced gas separation properties by using nanostructured PES‐Zeolite 4A mixed matrix membranes

AbstractThe polymer–zeolite mixed matrix membranes were fabricated by incorporating nanosized or microsized zeolite 4A into polyethersulfone. A comparison of zeolite 4A nanocrystals and microcrystals was made by using SEM, XRD, N2 adsorption–desorption measurements. Zeolite particles were well‐distributed in the polymer phase, as reflected by the SEM images. The effects of the zeolite 4A particle size on the gas permeation performance were studied. Experimental results demonstrate that mixed matrix membranes exhibit decreased gas permeabilities due to the barrier effect of zeolite particles. The obtained permselectivity is greatly enhanced for He/N2, H2/N2, He/CO2, and H2/CO2 gas pairs, especially for nanosized zeolite 4A mixed matrix membranes. The gas permeation performance difference is observed between the nanostructured and microstructured membranes, which is attributed to a combined effect of different zeolite composition and different particle size. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3800–3805, 2006

Effect of zeolite particle size on the performance of polymer–zeolite mixed matrix membranes

The effect of zeolite particle size on the performance of silicalite–PDMS mixed matrix membranes is investigated at two different zeolite loadings. The separation properties of the membranes prepared are characterized by permeability measurements for O 2, N 2 and CO 2 gases. The permeabilities of the silicalite–PDMS mixed matrix membranes are determined to increase with increasing particle size. The variations occurring in the permeability values with changes made in the particle size are much more pronounced at the higher zeolite loading. The ideal selectivity values corresponding to the mixed matrix membranes, on the other hand, generally seem to be less affected by the changes made in the particle size. The permeability values corresponding to the mixed matrix membranes exceed those pertaining to the original polymer membrane only at relatively higher zeolite loadings and/or for relatively larger particle sizes. The variations occurring in the permeabilities and selectivities with changes made in the zeolite particle size may be responsible for the different values of these parameters reported in the literature for the same types of zeolite filled polymeric membranes.