The mercury removal efficiency of a novel metal‐organic framework (MOF) derived from the amino acid S‐methyl‐L‐cysteine is presented and the process is characterized by single‐crystal X‐ray crystallography. A feasibility study is further presented on the performance of this MOF—and also that of another MOF derived from the amino acid L‐methionine—when used as the sorbent in mixed matrix membranes (MMMs). These MOF‐based MMMs exhibit high efficiency and selectivity—in both static and dynamic regimes—in the removal of Hg2+ from aqueous environments, due to the high density of thioalkyl groups decorating MOF channels. Both MMMs are capable to reduce different concentration of the pollutant to acceptable limits for drinking water (<2 parts per billion). In addition, a novel device, consisting of the recirculation and adsorption of contaminated solutions through the MOF–MMMs, is designed and successfully explored in the selective capture of Hg2+. Thus, filtration of Hg2+ solutions with multiple passes through the permeation cell shows a gradual decrease of the pollutant concentration. These results suggest that MOF‐based MMMs can be implemented in water remediation, helping to reduce either contaminants from accidental unauthorized or deliberate metal industrial dumping and to ensure access for clean and potable freshwater.

We report two new highly crystalline metal−organic frameworks (MOFs), derived from the natural amino acids serine (1) and threonine (2), featuring hexagonal channels densely decorated with hydroxyl groups belonging to the amino acid residues. Both 1 and 2 are capable of discriminating, via solid-phase extraction, a mixture of selected chloride salts of lanthanides on the basis of their size, chemical affinity, and/or the flexibility of the network. In addition, this discrimination follows a completely different trend for 1 and 2 because of the different locations of the hydroxyl groups in each compound, which is evocative of steric complementarity between the substrate and receptor. Last but not least, the crystal structures of selected adsorbates could be resolved, offering unprecedented snapshots on the capture process and enabling structural correlations with the separation mechanism.

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The aim of this project was to study the treatment of industrial waste using ETS-10 zeolite. The pollutants that must be removed were metals sourced from zinc ferrite, a processing waste derived from the use of mineral-containing zinc. The first phase of the work involved the characterization of the industrial waste, zinc ferrite, in order to deepen the knowledge regarding its nature and composition. The second phase involved the removal of the metals released by the zinc ferrite in aqueous systems using the ETS-10 phase as an ion exchanger. Different chemical and physical techniques were used: plasma mass spectrometry, X-ray diffraction, scanning electron microscopy, microanalysis, and thermal analyses. A comparison between ETS-10 and commercial zeolite A performance, in the same aqueous systems, was carried out. The results showed that the metal removal efficiency of ETS-10 phase is higher than that obtained by commercial zeolite A, especially towards dangerous heavy metals such as Pb, Zn and Mn.

In this work, a polydimethylsiloxane/divinylbenzene fiber overcoated with a layer of polydimethylsiloxane was evaluated as analytical sampling tool for the first time in human urine. Urinary polycyclic aromatic hydrocarbons with 2-6 aromatic rings were considered as target compounds. The analyte uptake in kinetic and thermodynamic regime was evaluated and compared to the performances of polydimethylsiloxane/divinylbenzene and polydimethylsiloxane fibers. The assessment of the robustness and endurance of the overcoated fiber was carried out by direct immersion solid-phase microextraction in undiluted urine performing up to 120 consecutive extractions. The overcoated fiber was then used to develop a fast and easy direct immersion solid-phase microextraction with gas chromatography and triple quadrupole mass spectrometry protocol for the quantification of the target polycyclic aromatic hydrocarbons. The attained values of accuracy and precision were 75-114% and 2-19%, respectively, while the limits of quantification ranged between 0.05 and 1 ng/L. The proposed protocol was applied to the screening of urine samples collected from smoking and nonsmoking volunteers. The successful results obtained by using the overcoated fiber create not only new alternatives for polycyclic aromatic hydrocarbon exposure assessment but also new perspectives for the application of direct immersion solid-phase microextraction to the analysis of bioclinical matrixes.