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The adsorption and separation of light n-alkane hydrocarbons (propane, butane, pentane, hexane and heptane) by zinc and cadmium hexacyanocobaltates (III) were studied from inverse gas chromatographic data. These two solids are representative of the porous frameworks found for transition metals hexacyanometallates. For cadmium, the porous framework is related to the presence of systematic vacancies for the building block, [Co(CN) 6 ], while for Zn it is a consequence of a tetrahedral coordination for the Zn atom. These linear light hydrocarbons (paraffins) are effectively separated by these two porous frameworks. The involved differential adsorption heats and the related separation coefficients were estimated from the recorded chromatographic data. No significant differences for the separation ability of light n-alkane hydrocarbons by the evaluated materials were observed.

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Two composites based on a Zn 2+ exchanged natural clinoptilolite and ZnO nanoparticles were obtained by mechanosynthesis and 'in situ' methods. Characterization of resulting materials was carried out using XRD, Raman spectroscopy, TGA, FE-SEM and N 2 adsorption. XRD results showed that no significant changes in the crystalline structure of the zeolite took place due to the performed treatments. Thermogravimetric behaviour indicated a high thermal stability for all samples. Raman spectra exhibited the characteristic bands for clinoptilolite zeolite and ZnO reported in the literature and the RRUFF database. Morphology changes were observed between natural and exchanged clinoptilolite and the 'in situ' obtained composite. Textural analysis showed a decrease in surface area of 'in situ' composite compared with the exchanged zeolites, related to the partial nanoparticle deposition in the pore entrances. The adsorption studies of methylene blue in the zeolitic samples and composites showed that all evaluated materials were able to absorb the dye from aqueous solutions.

In this work, a study of the secondary porosity of two zeolite‐based composites is carried out by small angle X‐ray scattering (SAXS) and N2 adsorption at 77 K. The composites were obtained by the inclusion of ZnO nanoparticles in a Cuban natural clinoptilolite by mechanosynthesis and ‘in situ’ methods. It was observed a decrease in the specific surface area as a result of ZnO nanoparticles inclusion from 149 m2 g−1 in the started material to 60 m2 g−1 in the composite prepared by in situ method, whereas the mesopore diameter remained almost constant. The results confirmed the presence of mesopores with diameter between 3 and 36 nm, with good match by both methodologies. These materials were developed in view of their future application as catalysts and adsorbents, where the presence of secondary porosity is key to favor the diffusion processes.