This work is part of a research project aimed at studying potential sorbents for CO₂ capture. The main parameters characterising the adsorption process of zeolite 13X were derived with the aim of overcoming the limits of experimental analysis and thus predicting the performances of the materials of interest. In particular, the main parameters that control the adsorption process of CO₂ in zeolite 13X were evaluated through parametric optimisation. This systematic procedure allows for the prediction of the performances of the materials at different operating conditions, identifying the most suitable ones for the case under consideration. Another important application lies in the possibility of a preliminary study of a potential process scale-up for future industrial use. The captured carbon dioxide can be stored or used as a reagent in the production of products with higher economic values, such as methanol, DME and others.

The recovery of lithium from extracts obtained from a black mass of spent lithium-ion batteries treated with a ternary solvent system at acidic pH was investigated using flat-sheet nanofiltration (NF) membranes operated according to a dead-end configuration. Specifically, four samples obtained at different pH values (2.5 and 5) and extraction times (48, 96 and 168 h) were treated in selected operating conditions by using two commercial polymeric membranes (denoted DK and HL, with an approximate molecular weight cut-off of 150–300 Da) up to a volume reduction factor (VRF) of 4. Membrane performance was assessed in terms of productivity and selectivity towards specific ions, including lithium. For most treated samples, the HL membrane exhibited higher permeate fluxes in comparison to the DK membrane. However, the DK membrane performed better in terms of lithium rejection than the HL membrane, with a negative rejection at VRF 4 observed for all treated samples. More than 90% of multivalent ions were rejected by both membranes independently of the VRF. The membrane ability to retain multivalent ions led to their progressive concentration in the retentate as the VRF increased. The extraction time did not impact the NF performance of both membranes in terms of ion rejection. For the DK membrane conditions of extraction of 96 h and pH 5 represented the best trade-off between flux, ion rejection, and total lithium recovery.

This study undertakes a thorough examination of hydrogen solubility within various metal-alloy membranes, including those based on palladium (Pd), vanadium (V), niobium (Nb), tantalum (Ta), amorphous alloys and liquid gallium (Ga). The analysis aims to outline the strengths and weaknesses of each material in terms of solubility and permeability performance. The investigation began by acknowledging the dual definitions of solubility found in literature: the “secant method”, which calculates solubility based on the hydrogen pressure corresponding to a specific sorbed hydrogen loading, and the “tangent method”, which evaluates solubility as the derivative (differential solubility) of the sorption isotherm at various square root values of hydrogen partial pressure. These distinct methodologies yield notably different outcomes. Subsequently, a compilation of experimental data for each membrane type is gathered, and these data are re-analysed to assess both solubility definitions. This enabled a clearer comparison and a deeper analysis of membrane behaviour across different conditions of temperature, pressure, and composition in terms of hydrogen solubility in the metal matrix. The re-evaluation presented in this study serves to identify the most suitable membranes for hydrogen separation or storage, as well as to pinpoint the threshold of embrittlement resulting from hydrogen accumulation within the metal lattice. Lastly, recent research has indicated that particularly promising membranes are those fashioned as “sandwich” structures using liquid gallium. These membranes demonstrate resistance to embrittlement while exhibiting superior performance characteristics.

Understanding the early-stage physical interactions between polymeric membranes and supersaturated salt solutions is crucial for advancing membrane-assisted crystallization (MCr) processes. In this study, we employed molecular dynamics (MD) simulations to investigate the short-term morphological response of an isotactic polypropylene (PP) membrane in contact with LiF solutions at different concentrations (5.8 M and 8.9 M) and temperatures (300–353 K), across multiple time points (0, 150, and 300 ns). These data were used as input for computational fluid dynamics (CFD) analysis to evaluate structural descriptors of the membrane, including tortuosity, connectivity, void fraction, anisotropy, and deviatoric anisotropy, under varying thermodynamic conditions. The results show subtle but consistent rearrangements of polymer chains upon exposure to the hypersaline environment, with a marked reduction in anisotropy and connectivity, indicating a more compact and isotropic local structure. Surface charge density analyses further suggest a temperature- and concentration-dependent modulation of chain mobility and terminal group orientation at the membrane–solution interface. Despite localized rearrangements, the membrane consistently maintains a net negative surface charge. This electrostatic feature may influence ion–membrane interactions during the crystallization process. While these non-reactive, short-timescale simulations do not capture long-term degradation or fouling mechanisms, they provide mechanistic insight into the initial physical response of PP membranes under MCr-relevant conditions. This study lays a computational foundation for future investigations bridging atomistic modeling and membrane performance in real-world applications.