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SBA-15 mesoporous silica was functionalized with polyethylenimine and was used as a substrate for CO 2 adsorption. The synthesized material, denoted SBA-15-PEI, was characterized by means of X-ray diffraction, thermogravimetric analysis, and N 2 adsorption/desorption at 77 K, in order to prove that polymer chains efficiently filled the pores of functionalized samples. CO 2 adsorption isotherms on SBA-15-PEI were evaluated at T = (298, 313, 328, and 348) K for pressures up to 100 kPa by means of a volumetric technique. The experimental data showed a significant dependence of the CO 2 adsorption capacity on temperature, with the highest capacity encountered at the highest temperature explored. Despite this unusual behavior, CO 2 adsorption on SBA-15-PEI was satisfactorily modeled by means of the Sips isotherm. The modeling effort allowed to evaluate the isosteric heat of adsorption as a function of the fractional coverage of SBA-15-PEI. The comparison between the results obtained in the present work and those relative to CO 2 adsorption on "benchmark" microporous substrates, such as 13X zeolite and Cu-BTC metal organic framework, allowed us to highlight significant analogies and differences with those other solids, giving interesting hints on the possible applications of SBA-15-PEI.

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In this work, a chromium-based metal organic framework (Cr-MOF) was synthesized, characterized and tested for the adsorption of a model highly ozone-depleting anaesthetic (sevoflurane). Adsorption isotherms were measured at different temperatures e.g., 283, 298, 313 and 328 K on both Cr-MOF and a conventionally used reference adsorbent. At the temperatures used in this study, the Cr-based MOF showed a significantly higher sevoflurane (selected anaesthetic) equilibrium adsorption capacity compared to the reference sample, although adsorption on the selected MOF did not take place on all active sites (i.e., it did not expose its coordinatively unsaturated sites). Moreover, sevoflurane adsorption on Cr-MOF was found to be fully reversible in the 283–328 K temperature range, and the adsorbent was fully regenerated by vacuum treatment at ambient temperature. The semiempirical Sips model was successfully used to fit sevoflurane adsorption data, substantially confirming the phenomenological aspects of the process inferable from the experimental results

A synthesized chromium-based metal organic framework (Cr-MOF) was used for the adsorption of halogenated anesthetics, i.e., sevoflurane (SF). Adsorption isotherm and breakthrough experiments involving SF (reference sorbate) and water vapor were measured at 298 K and atmospheric pressure on both Cr-MOF and a commercially used reference adsorbent. The Cr-MOF MIL-101 showed a significantly higher SF adsorption capacity and much higher selectivity relative to water vapor compared to the reference adsorbent. Binary-mixture breakthrough tests demonstrated a ''roll-up effect'' for SF on the reference adsorbent while no such effect was observed on MIL-101.