UiO-66-GO hybrids were obtained by hydrothermal synthesis of MOF UiO-66 (a Zr terephthalate) on graphite oxide (GO). These hybrids with appropriate texture and presence of nanosized MOF particles (in the ca. 30-100 nm range) have been used as fillers to prepare mixed matrix membranes (MMMs) with two different polymers, polysulfone (PSF) and polyimide (PI), as the matrixes, with contents varying between 0 and 32 wt%. The MMMs were applied to the separation of H 2 /CH 4 and CO 2 /CH 4 mixtures at different temperatures (35, 60 and 90 ºC). Besides finding a good filler-polymer interaction, in the particular case of the hybrid filler, the barrier effect of the GO and the microporosity of the MOF dominated the separation properties of the MMMs. In all cases (different MMMs and separation mixtures) the effect of the temperature was to increase the permeability with a simultaneous decrease in the corresponding selectivity. In terms of permselectivity, the best H 2 /CH 4 separation results were obtained (at 35 ºC) with a PI based MMM containing only UiO-66 as filler (H 2 permeability of 73 Barrer and H 2 /CH 4 selectivity of 151), while a hybrid UiO-66-GO filler produced the best CO 2 /CH 4 performance (CO 2 /CH 4 selectivity value of 51 at 21 Barrer of CO 2), also using a PI polymer.

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JDF-L1 is a microporous layered titanosilicate. JDF-L1-based composite materials have been prepared by melt compounding commercial polysulfone together with swollen JDF-L1 at a temperature gradient of 303−340 °C. During the melt compounding process most of the swollen JDF-L1 was exfoliated, confirmed by thermal, TEM, and XRD analyses. The exfoliated JDF-L1/polysulfone master batch was diluted in polysulfone to obtain mixed matrix membranes (MMMs) with inorganic loadings in the 0−9.5 wt % range, in which exfoliated JDF-L1 particles were well dispersed. The MMMs were applied to the separation of a H 2 /CH 4 mixture with an improved performance as compared to the pure polymer or to chemically exfoliated JDF-L1/polysulfone membranes. The best performance obtained in this work corresponds to an 8.3 wt % MMM with H 2 permeability and H 2 /CH 4 selectivity of 12.5 Barrer and 128, respectively.