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RICCARDO FANTINI
Ricercatore t.d. art. 24 c. 3 lett. A
Dipartimento di Scienze Chimiche e Geologiche - Sede Dipartimento di Scienze Chimiche e Geologiche
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Pubblicazioni
2024
- An insight into REEs recovery from spent fluorescent lamps: Evaluation of the affinity of an NH4-13X zeolite towards Ce, La, Eu and Y
[Articolo su rivista]
Colombo, Francesco; Fantini, Riccardo; Di Renzo, Francesco; Malavasi, Gianluca; Malferrari, Daniele; Arletti, Rossella
abstract
The constantly increasing demand of Rare Earth Elements (REEs) made them to be part of the so-called "critical elements" indispensable for the energy transition. The monopoly of only a few countries, the so-called balance problem between demand and natural abundance, and the need to limit the environmental costs of their mining, stress the necessity of a recycling policy of these elements. Different methods have been tested for REEs recovery. Despite the well-known ion-exchange properties of zeolites, just few preliminary works investigated their application for REEs separation and recycle. In this work we present a double ion exchange experiment on a NH4-13X zeolite, aimed at the recovery of different REEs from solutions mimicking the composition of liquors obtained from the leaching of spent fluorescent lamps. The results showed that the zeolite was able to exchange all the REEs tested, but the exchange capacity was different: despite Y being the more concentrated REE in the solutions, the cation exchange was lower than less concentrated ones (16 atoms p.u.c. vs 21 atoms for Ce and La solutions), suggesting a possible selectivity. In order to recover REEs from the zeolite, a second exchange with an ammonium solution was performed. The analyses of the zeolites show that almost all of Ce and Eu remain in the zeolite, while nearly half of La and Y are released. This, once again, suggests a possible selective release of REEs and open the possibility for a recovery process in which Rare Earths can be effectively separated.
2024
- Reappraisal of red clays in porcelain stoneware production: Compositional and technological characterization
[Articolo su rivista]
Fantini, Riccardo; Conte, Sonia; Gualtieri, Alessandro F.; Dondi, Michele; Colombo, Francesco; Sisti, Mattia; Molinari, Chiara; Zanelli, Chiara; Arletti, Rossella
abstract
2023
- The beneficial role of nano-sized Fe3O4 entrapped in ultra-stable Y zeolite for the complete mineralization of phenol by heterogeneous photo-Fenton under solar light
[Articolo su rivista]
Tammaro, Olimpia; Morante, Nicola; Marocco, Antonello; Fontana, Marco; Castellino, Micaela; Barrera, Gabriele; Allia, Paolo; Tiberto, Paola; Arletti, Rossella; Fantini, Riccardo; Vaiano, Vincenzo; Esposito, Serena; Sannino, Diana; Pansini, Michele
abstract
: Highly efficient, separable, and stable magnetic iron-based-photocatalysts produced from ultra-stable Y (USY) zeolite were applied, for the first time, to the photo-Fenton removal of phenol under solar light. USY Zeolite with a Si/Al molar ratio of 385 was impregnated under vacuum with an aqueous solution of Fe2+ ions and thermally treated (500-750 °C) in a reducing atmosphere. Three catalysts, Fe-USY500°C-2h, Fe-USY600°C-2h and Fe-USY750°C-2h, containing different amounts of reduced iron species entrapped in the zeolitic matrix, were obtained. The catalysts were thoroughly characterized by absorption spectrometry, X-ray powder diffraction with synchrotron source, followed by Rietveld analysis, X-ray photoelectron spectroscopy, N2 adsorption/desorption at -196 °C, high-resolution transmission electron microscopy and magnetic measurements at room temperature. The catalytic activity was evaluated in a recirculating batch photoreactor irradiated by solar light with online analysis of evolved CO2. Photo-Fenton results showed that the catalyst obtained by thermal treatment at 500 °C for 2 h under a reducing atmosphere (FeUSY-500°C-2h) was able to completely mineralize phenol in 120 min of irradiation time at pH = 4 owing to the presence of a higher content of entrapped nano-sized magnetite particles. The latter promotes the generation of hydroxyl radicals in a more efficient way than the Fe-USY catalysts prepared at 600 and 750 °C because of the higher Fe3O4 content in ultra-stable Y zeolite treated at 500 °C. The FeUSY-500°C-2h catalyst was recovered from the treated water through magnetic separation and reused five times without any significant worsening of phenol mineralization performances. The characterization of the FeUSY-500°C-2h after the photo-Fenton process demonstrated that it was perfectly stable during the reaction. The optimized catalyst was also effective in the mineralization of phenol in tap water. Finally, a possible photo-Fenton mechanism for phenol mineralization was assessed based on experimental tests carried out in the presence of scavenger molecules, demonstrating that hydroxyl radicals play a major role.
2023
- Unraveling the Molecular Structure of Zeolite–Octyl Methoxycinnamate Hybrid UV Filters: A Combined Spectroscopic and Computational Approach
[Articolo su rivista]
Fischer, Michael; Fantini, Riccardo; Arletti, Rossella; Brauer, Jakob; Mino, Lorenzo
abstract
In this contribution, we tried to shed light on the molecular structure of octyl methoxycinnamate (octinoxate, OMC) adsorbed in NaX zeolite, which represents a promising hybrid UV filter system. The combination of infrared spectroscopy and density functional theory modeling was crucial to identify all the complex host-guest interactions and to unveil that, although slightly thermodynamically unfavored, OMC is dominantly present in the trans-form inside the NaX framework. We also showed that the interaction between the zeolite Na cations and the OMC molecule is the key feature that determines the stability and efficacy of these hybrid UV filters. These findings confirm that cationic zeolites are promising materials for the encapsulation of UV filters to decrease their negative impact on the environment and their photochemical instability.
2022
- Structural evidence of sunscreen enhanced stability in UV filter-Zeolite hybrids
[Articolo su rivista]
Confalonieri, G.; Fantini, R.; Allasia, N.; Vezzalini, G.; Fitch, A. N.; Mino, L.; Arletti, R.
abstract
Organic UV filters are used in many applications (personal-care products, components in packaging, dyes, etc). However, many issues remain related to their safety; their release into the environment is toxic for many organisms and their photodegradation products are possibly dangerous. Encapsulation of these molecules in a zeolitic matrix can avoid their dispersion and promote the enhancement of their properties. In this study, we report the structural characterization of the new LTL/OMC ZEOfilter, produced by encapsulating the organic UV filter octinoxate (OMC, C18H26O3) into synthetic zeolite L. In fact, for the further exploitation and the realization of tailor-made materials, it is fundamental to understand the interactions between the filter and the matrix. X ray powder diffraction, Rietveld structural analysis and Monte Carlo simulations result in a detailed description of the molecules’ setting and configuration. To fit the pores of the zeolite, the conformation of OMC molecules assumes a bent tail, allowing suitable intermolecular distances and host-guest interactions. These results were also corroborated by FT-IR experiments. The host-guest interaction is the key point for the stability and efficacy of LTL/OMC ZEOfilter and may explain why, among different ZEOfilters, the cationic zeolites, and especially zeolite L, display the most promising features.
2021
- Boosting sunscreen stability: New hybrid materials from UV filters encapsulation
[Articolo su rivista]
Fantini, Riccardo; Vezzalini, Giovanna; Zambon, Alfonso; Ferrari, Erika; Di Renzo, Francesco; Fabbiani, Marco; Arletti, Rossella
abstract
2021
- Steering polymer growth by molding nanochannels: 1,5-hexadiene polymerization in high silica mordenite
[Articolo su rivista]
Fabbiani, M.; Confalonieri, G.; Morandi, S.; Arletti, R.; Quartieri, S.; Santoro, M.; Di Renzo, F.; Haines, J.; Fantini, R.; Tabacchi, G.; Fois, E.; Vezzalini, G.; Ricchiardi, G.; Martra, G.
abstract
Zeolites are known as scaffolds for the assembly of molecules via non-covalent interactions yielding organized supramolecular materials. Yet their potential in driving the growth of low-dimensional systems requiring covalent bond formation is still unexplored. We incorporated 1,5-hexadiene in the channels of a high-silica mordenite and analyzed the material by infrared spectroscopy, X-ray powder diffraction, thermogravimetry and modeling techniques. Due to the few zeolite acid sites, 1,5-hexadiene experiences a slow conversion to a polymer mainly formed by cyclopentane units and featuring short side chains that are able to fit the channels. The shape-directing abilities of zeolite frameworks play a two-fold role, involving first the organization of the monomers inside the void-space and then the linear growth of the chain dictated by the channel geometry. These findings highlight the molding action of zeolites in directing transformations of covalent bonds under ambient conditions and may provide insights for obtaining confined polymers with intriguing prospective applications.
2020
- Thermal behavior of high silica mordenite
[Articolo su rivista]
Fantini, Riccardo; Arletti, Rossella; Quartieri, Simona; Fabbiani, Marco; Morandi, Sara; Martra, Gianmario; Di Renzo, Francesco; Vezzalini, Maria Giovanna
abstract
This work studies the thermal stability, heat-induced structural deformations, and dehydration/rehydration
dynamics of a synthetic high silica mordenite. It is of special interest because this particular phase has proven to
be an ideal host for the encapsulation of several kinds of organic molecules making it a promising scaffold for
drug delivery. The dehydration process was followed by thermal analysis, infrared spectroscopy in controlled
atmosphere, in situ synchrotron XRPD, and structural refinement. Overall, all the results indicate weak interactions
of H2O molecules with the silicatic mordenite framework and evidence the presence of hydroxyl
groups with different condensation responses at high temperature. Infrared characterization highlighted how the
desorption of adsorbed H2O molecules under degassing is already complete at rT. The unit cell parameters
exhibit very slow and almost isotropic changes upon heating. Above 550 �C an increase in slope is observed for
all parameters. This corresponds to the marked silanol condensation and consequent framework reassessment
observed at this temperature by infrared characterization. Overall cell contractions are 0.67%, 1.18%, and 0.81%
for a, b, c, respectively and 2.64% for cell volume. HS-MOR undergoes very moderate T induced deformations,
indicating a very rigid and stable framework.
2019
- Insertion and Confinement of H2O in Hydrophobic Siliceous Zeolites at High Pressure
[Articolo su rivista]
Santoro, Mario; Veremeienko, Vasyl; Polisi, Michelangelo; Fantini, Riccardo; Alabarse, Frederico; Arletti, Rossella; Quatieri, Simona; Svitlyk, Volodymyr; van der Lee, Arie; Rouquette, Jérôme; Alonso, Bruno; Di Renzo, Francesco; Coasne, Benoît; Haines, Julien
abstract
2019
- Thermal Behavior of Synthetic High-Silica Mordenite
[Poster]
Fantini, Riccardo; Arletti, Rossella; Quartieri, Simona; Fabbiani, Marco; Morandi, Sara; Martra, Gianmario; Di Renzo, Francesco; Vezzalini, Giovanna
abstract
2018
- Dehydration Mechanism of Monastir Ferrierite: a High Resolution In-situ X-ray Powder Diffraction Study
[Poster]
Fantini, Riccardo; Arletti, Rossella; Gieré, Reto; Vezzalini, Giovanna; Vigliaturo, Ruggero; Quartieri, Simona
abstract
2018
- Dehydration and high temperature behavior of zeolite ferrierite
[Poster]
Fantini, Riccardo; Arletti, Rossella; Quartieri, Simona; Polisi, Michelangelo; Giacobbe, Carlotta; Vezzalini, Giovanna
abstract
2018
- High temperature behavior of zeolite ferrierite: in situ synchrotron X-ray powder diffraction study
[Poster]
Fantini, Riccardo; Arletti, Rossella; Gieré, Reto; Polisi, Michelangelo; Vezzalini, Giovanna; Vigliaturo, Ruggero; Quartieri, Simona
abstract
2018
- High-temperature behavior of natural ferrierite: In-situ synchrotron X-ray powder diffraction study
[Articolo su rivista]
Rossella, Arletti; FANTINI, RICCARDO; Carlotta, Giacobbe; Reto, Gieré; VEZZALINI, Maria Giovanna; Ruggero, Vigliaturo; Simona, Quartieri; ARLETTI, Rossella
abstract
In this paper, we report the results of the first study focused on the thermal stability and dehydration dynamics of the natural zeolite mineral ferrierite. A sample from Monastir, Sardinia [(Na0.56K1.19Mg2.02Ca0.52 Sr0.14) (Al6.89Si29.04)O72∙17.86H2O; a = 19.2241(3) Å; b = 14.1563(2) Å; c = 7.5106(1) Å, V = 2043.95(7) Å3] was investigated by thermogravimetric analysis and in-situ synchrotron X‑ray powder diffraction. Thermogravimetric data show that H2O release begins already in the range 50–100 °C and is complete at ~600 °C. The results of the structure refinements performed in Immm space group by Rietveld analysis with data collected up to 670 °C show that ferrierite belongs to the group of zeolites that do not undergo phase transitions. Upon heating to 670 °C, ferrierite behaves as a non-collapsible structure displaying only a slight contraction of the unit-cell volume (DV = –3%). The unit-cell parameter reductions are anisotropic, more pronounced for a than for b and c (Da = –1.6%; Db = –0.76%; Dc = –0.70%). This anisotropic response to a temperature increase is interpreted as due to the presence in the ferrierite framework of five-membered ring chains of SiO4 tetrahedra, which impart a higher structural rigidity along b and c. Upon dehydration we observe: (1) the gradual H2O loss, beginning with the molecules hosted in the 10MR channel, is almost complete at 670 °C, in good agreement with the TG data; (2) as a consequence of the decreased H2O content, Mg and K migrate from their original positions, moving from the center of the 10MR channel toward the walls to coordinate the framework oxygen atoms. The observation of transmission electron microscopy selected-area electron diffraction patterns revealed defective crystals with an occasional and moderate structural disorder. Beyond providing information on the thermal stability and behavior of natural ferrierite, the results of this work have significant implications for possible technological applications. These data allow for comparison with the dehydration kinetics/mechanisms of the corresponding synthetic phases, clarifying the role played by framework and extra-framework species on the high-temperature behavior of porous materials with ferrierite topology. Moreover, the information on the thermal behavior of natural ferrierite can be used to predict the energetic performances of analogous synthetic Si-pure counterparts, namely “zeosil-electrolyte” systems, under non-ambient conditions. Specifically, the very high thermal stability of ferrierite determined in this study, coupled with the baric behavior determined in other investigations, suggests that the “Si-FER–electrolyte” system may be an excellent candidate for use as an energy reservoir. Indeed, ferrierite exhibits the so-called “spring behavior,” i.e., upon compression in water or in an electrolyte solution, it converts the mechanical energy into interfacial energy, and—when pressure is released—it can completely restore the supplied mechanical energy accumulated during the compression step.
2018
- Sasbach Faujasite: structural refinement of natural and NH4-exchanged phase and preliminary results on crystal dealumination
[Poster]
Fantini, R.; Arletti, R.; Pastero, L.; Quartieri, S.; Di Renzo, F.; Camara, F.; Vezzalini, G
abstract
2018
- Structure of Natural and NH4-Exchanged Sasbach Faujasite: a single crystal study
[Poster]
Fantini, R.; Arletti, R.; Pastero, L.; Quartieri, S.; Di Renzo, F.; Cámara, F.; Vezzalini, G.
abstract
2018
- Structure of natural and NH4-exchanged Sasbach faujasite: a single-crystal study
[Articolo su rivista]
Fantini, Riccardo; Rossella, Arletti; Linda, Pastero; Simona, Quartieri; Francesco Di Renzo, ; Fernando, Cámara; Vezzalini, Maria Giovanna; Arletti, Rossella
abstract
The interest for the environmental, industrial and technological applications of Si-rich zeolites is very high. Among the large-pore zeolites, faujasite is one of the most exploited. The aim of this paper is to obtain detailed structural information on natural and NH4-exchanged faujasite before using this zeolite for dealumination tests, targeting the realization of large single crystals of all-silica faujasite. As one of the most Si-rich natural samples, faujasite from Sasbach (Na13.64K0.87Mg10.46Ca8.89Sr0.34(Al51.95Si139.57)O384∙272.29 H2O; space group Fd-3m;a = 24.6906(2) Å) was chosen for study. Single-crystal X-ray diffraction structural refinements of both natural and NH4-exchanged samples are reported and discussed. In the natural faujasite sample, almost all the extraframework species could be located for the first time. In the NH4-exchanged sample the ammonium and water molecule sites were located. Ammonium cations occupy two of the sites occupied by the extraframework species in the original mineral.
2016
- Clay in Baiso (Reggio Emilia), between problem and resource: An educational path in the 1st grade secondary school
[Articolo su rivista]
Scacchetti, M.; Fantini, R.
abstract
2014
- Le argille, protagoniste del paesaggio attorno a Baiso (RE)
[Abstract in Atti di Convegno]
Scacchetti, Maurizio; Fantini, Riccardo
abstract