Papers by Giovanni Dotelli
Buildings
Due to our increasing dependence on resources and energy, climate change is among the most tangib... more Due to our increasing dependence on resources and energy, climate change is among the most tangible issues we are facing today. The construction industry has been identified as a key sector to intervene in, but mitigation strategies must focus on more than just operational energy. As current climate policies recommend, designers should consider the broader framework of environmental impacts characterizing the entire building lifecycle. Life Cycle Assessment (LCA) considers the mentioned aspects. Nevertheless, the complexity of LCA and the criticalities of related tools prevent the application of the approach during decisive early stages. Additionally, LCA allows the estimation of environmental issues, but fails to describe other dimensions of sustainability. The article proposes an evaluation method to support decision-making during the design of sustainable buildings. The method exploits the LCA tool and the assessment framework provided by a Green Sustainable Building Certificatio...
Nanomaterials
This work reports the preliminary results of the development of composite self-assembling membran... more This work reports the preliminary results of the development of composite self-assembling membranes obtained by the combination of reduced graphene oxide (rGO) with commercial Degussa P25 titanium dioxide (TiO2). The purpose is to demonstrate the possibility of combining, in the same self-standing material, the capability to treat wastewater containing both inorganic and organic pollutants by exploiting the established ability of rGO to capture metal ions together with that of TiO2 to degrade organic substances. Moreover, this study also investigates the potential photocatalytic properties of tionite (TIO), to demonstrate the feasibility of replacing commercial TiO2 with such waste-derived TiO2-containing material, fulfilling a circular economy approach. Thus, rGO–TiO2 and rGO–TIO composite membranes, 1:1 by weight, were prepared and characterized by SEM-EDX, XRD, thermogravimetry, as well as by Raman and UV-Vis spectroscopies to verify the effective and homogeneous integration of t...
Clean Technologies
Despite being the most employed polymer electrolyte for proton exchange membrane fuel cells (PEMF... more Despite being the most employed polymer electrolyte for proton exchange membrane fuel cells (PEMFCs), Nafion® has several limitations: expensiveness, poor performance when exposed to temperatures higher than 80 °C, and its potential as a source of environmentally persistent and toxic compounds (i.e., per- and polyfluoroalkyl substances, known as PFASs) when disposed of. This work explores the functional and environmental performances of three potential PFAS-free alternatives to Nafion® as electrolytic membranes in PEMFCs: sulfonated graphene oxide (SGO), graphene oxide-naphthalene sulfonate (GONS), and borate-reinforced sulfonated graphene oxide (BSGO). Investigated via ATR-FTIR spectroscopy, TGA, and cross-sectional SEM, the membranes show an effective functionalization of GO and good thermal stability. Functional properties are determined via Ion Exchange Capacity (IEC) evaluation, Electrochemical Impedance Spectroscopy, and tensile tests. In terms of IEC, the innovative materials...
Materials
Interest towards cellulose nanofibers obtained from virgin and waste sources has seen a significa... more Interest towards cellulose nanofibers obtained from virgin and waste sources has seen a significant growth, mainly thanks to the increasing sensitivity towards the concept of circular economy and the high levels of paper recycling achieved in recent years. Inspired by the guidelines of the green building industry, this study proposes the production and characterization of TEMPO-oxidized and homogenized cellulose nanofibers (TOHO CNF) from different sources and their use as additives for earth plasters on two different raw earth samples, characterized by geotechnical laboratory tests and mineralogical analysis: a high-plasticity clay (T2) and a medium-compressibility silt (ABS). Original sources, including those derived from waste (recycled cardboard and paper mill sludge), were characterized by determining chemical content (cellulose versus ashes and lignin) and fiber morphology. TOHO CNF derived from the different sources were compared in terms of nanofibers medium diameter, crysta...
Polymers
This study is a starting point for the development of an efficient method for rare earths (REs) a... more This study is a starting point for the development of an efficient method for rare earths (REs) and transition metals (TMs) recovery from waste electrical and electronic equipment (WEEE) via a hydrometallurgical process. The capture and release capability of mineral clays (STx) and activated carbons (AC), pristine and modified (STx-L6 and AC-L6) with a linear penta-ethylene-hexamine (L6), towards solutions representative of the process, are assessed in the lab-scale. The solids were contacted with synthetic mono- and bi-ionic solutions containing Ni(II) and La(III) in a liquid/solid adsorption process. Contacting experiments were carried out at room temperature for 90 min by fixing a La concentration at 19 mM and varying the Ni one in the range of 19–100 mM. The four solids were able to capture Ni(II) and La(III), both in single- and bi-ionic solutions; however, the presence of the polyamine always results in a large improvement in the capture capability of the pristine sorbents. Fo...
Frontiers in Sustainability
The diffusion of Battery Electric Vehicles (BEVs) is projected to influence the electricity grid ... more The diffusion of Battery Electric Vehicles (BEVs) is projected to influence the electricity grid operation, potentially offering opportunities for load-shifting policies aimed at higher integration of renewable energy technologies in the electricity system. Moreover, the examined literature emphasizes electricity as a relevant driver of BEVs Life Cycle Assessment (LCA) results. To evaluate LCA impacts associated to future BEVs diffusion scenarios in Italy, we adopt the Consequential Life Cycle Assessment (CLCA) methodology. LCA conventionally assumes a proportional relation between environmental impact indicators and the functional unit. However, such relation may not be representative if the electricity system is significantly affected by the large-scale diffusion of BEVs. Our study couples the conventional CLCA methodology with the EnergyPLAN model through three different approaches, which progressively include BEV-specific dynamics, to capture correlations between additional BEVs...
Acta Polytechnica CTU Proceedings
Up to 500 litres of water may be consumed at the batching plant per cubic meter of ready mix conc... more Up to 500 litres of water may be consumed at the batching plant per cubic meter of ready mix concrete, if water for washing mixing trucks and equipment is included. Demand for concrete is growing almost everywhere, regardless of local availability of freshwater. The use of freshwater for concrete production exacerbates stress on natural water resources. In water-stressed coastal countries such as Israel, desalinated seawater (DSW) is often used in the production of concrete. However, the environmental impacts of this practice have not yet been assessed. In this study the effect of using DSW on the water and carbon footprints of concrete was investigated using life cycle assessment. Water footprint results highlight the benefits of using DSW rather than freshwater to produce concrete in Israel. In contrast, because desalination is an energy intensive process, using DSW increases the greenhouse gas intensity of concrete. Nevertheless, this increase (0.27 kg CO2e/m3 concrete) is small,...
The global construction sector face the need of adapting to climate change and at the same time t... more The global construction sector face the need of adapting to climate change and at the same time to shift the industry towards decarbonisation, decreasing the energy use in buildings in order to comply to international regulations. Every country that undersigned the Paris Agreement is expected to stablish decreasing goals for energy consumption and carbon emission according to their economic reality. Construction materials aiming energy saving, electricity consumption and carbon emission are deeply connected because one can be accounted for the increase of the previous two. Constructions materials are held to be the higher title of carbon emission source since the
Lubricants, 2022
Innovative nanostructured materials offer the possibility of enhancing the tribological performan... more Innovative nanostructured materials offer the possibility of enhancing the tribological performance of traditional materials like graphite and molybdenum disulfide (MoS2). In this study, the scratch resistance of two different copper powders, dendritic and spherical, and their composites with traditional MoS2, nanometric MoS2, and graphene nanoplatelets was investigated. Metal powder metallurgy was employed to produce composite materials with 5 wt% and 10 wt% of each solid lubricant. A ball milling step was employed to grind and mix the matrix copper powder with the lubricants. The use of a cold press combined with the sintering in inert atmosphere at 550 °C limited the oxidation of the copper and the degradation of the solid lubricants. The so-produced materials were characterized through a variety of techniques such as micro-indentation hardness, electrical resistivity, contact angle wettability, X-ray diffraction, Raman scattering, and scanning electron microscopy. Moreover, micr...
Minerals, 2020
This work focuses on the investigation of the capability of reduced graphene oxide (rGO) filters ... more This work focuses on the investigation of the capability of reduced graphene oxide (rGO) filters to remove metals from various wastewater. The process to produce rGO membranes is reported and discussed, as well as their ability to capture ions in complex solutions, such as tap or industrial wastewater. Multi-ion solutions, containing Cu2+, Fe3+, Ni2+, and Mn2+ to simulate mine wastewater, or Ca2+ and Mg2+ to mimic drinkable water, were used as models. In mono-ionic solutions, the best capture efficiency values were proved for Ca2+, Fe3+, and Ni2+ ions, while a matrix effect was found for multi-ion solutions. However, interesting capture efficiencies were measured in the range of 30–90%, depending on the specific ion, for both single and multi-ion solutions. An attempt is proposed to correlate ions capture efficiency with ions characteristics, such as ionic radius or charge. Combining a satisfactory capture efficiency with low costs and ease of treatment unit operations, the approach...
Molecules, 2022
This work deals with the development of graphene oxide (GO)-based self-assembling membranes as po... more This work deals with the development of graphene oxide (GO)-based self-assembling membranes as possible innovative proton conductors to be used in polymer electrolyte membrane fuel cells (PEMFCs). Nowadays, the most adopted electrolyte is Chemours’ Nafion; however, it reveals significant deficiencies such as strong dehydration at high temperature and low humidity, which drastically reduces its proton conductivity. The presence of oxygenated moieties in the GO framework makes it suitable for functionalization, which is required to enhance the promising, but insufficient, proton-carrying features of GO. In this study, sulfonic acid groups (–SO3H) that should favor proton transport were introduced in the membrane structure via a reaction between GO and concentrated sulfuric acid. Six acid-to-GO molar ratios were adopted in the synthesis procedure, giving rise to final products with different sulfonation degrees. All the prepared samples were characterized by means of TGA, ATR-FTIR and ...
Today there is an increasing need for Rare Earths (REs) due to their usage in numerous high-techn... more Today there is an increasing need for Rare Earths (REs) due to their usage in numerous high-technology applications. Each of these applications requires specific RE elements and they are not all interchangeable. Increasing demand for the different products containing REs has resulted in a restriction of supply from producing Countries, particularly China, which currently produces 97% of the world’s REs. This constriction of supply is being met by the development of many new REs mining projects which are characterized, however, by technical, economic and environmental problems (Binnemans et al., 2013). Currently each EU citizen produces about 17 kg of Waste Electric and Electronic Equipment (WEEE) per year. According to European Union estimates, this value is expected to rise to 24 kg by 2020. These wastes are rich in precious and strategic metals and, in many cases, are characterized by higher REs contents than those of natural minerals. Accordingly, recycling can be considered a va...
Two natural smectite clays (STx-1b and SWy-2) were studied as solid sorbents for uptake and relea... more Two natural smectite clays (STx-1b and SWy-2) were studied as solid sorbents for uptake and release of lanthanum. Since the obtained global efficiencies of lanthanum recovery were about 30-35%, the same considered natural clays were modified by intercalating a PEGylated ethylene diamine having chelating properties, in order to evaluate a possible improvement effect of the polymer. The pristine and the organo-clays were characterized by XRD analyses while the amounts of intercalated polymer and captured lanthanum were estimated respectively by COD and ICP-OES analyses. The results showed that pristine clays and modified clay had similar lanthanum uptake efficiencies while modified clays presented a better behaviour towards release processes, ensuring a recovery global efficiency of 43%.
In this work, Ca-montmorillonite (STx), natural and modified (STx-L6) with a linear penta-ethylen... more In this work, Ca-montmorillonite (STx), natural and modified (STx-L6) with a linear penta-ethylene-hexamine (L6), were tested as sorbents in a liquid/solid process for La and Cu capture in bionic model solutions. Twelve La/Cu ratios in solution were set and analyzed with the final target of investigating the capture mechanisms when both Cu and La are present. The liquid phase was characterized via inductively coupled plasmaoptical emission spectroscopy (ICP-OES), while the solids were studied by means of X-ray powder diffraction (XRPD). No direct competition between Cu and La ions for the capture sites was found but rather the modification of the acid−base condition of the solution and the related equilibria due to aquo-and hydroxycopper complexes formation. Cu complexes are responsible for pH modification and the related influence on the capture of La ions. Three distinct mechanisms were identified to be active in the capture process, i.e., ion exchange, surface adsorption, and coordination of the metal by the polyamine, when present. Only La is involved in the ionic exchange process, since no Cu was captured by pristine clays, while only Cu is coordinated to the polyamine, in view of its preferential interaction with amino groups. The different capture mechanisms are responsible for the higher efficiency of the organoclay, with respect to the pristine one. This study lays the groundwork for the development of an efficient method for rare earths (REs) and precious metal recovery from waste electrical and electronical equipment (WEEE) by a liquid/solid process.
Journal of Environmental Chemical Engineering, 2021
Uptake and release capability of a new organoclay material were assessed with the final goal to e... more Uptake and release capability of a new organoclay material were assessed with the final goal to evaluate its applicability in recovering REs from solutions. Capture and release capability have been tested towards a La ions model solution, and interaction mechanism and reactions, active in both capture and release processes, were related to the nature of the organoclay and the operating process parameters. The studied system, polyaminebased organoclay, is able to capture and release La ions with high efficiency. Capture involves three distinct mechanisms: ion exchange reaction with interlayer cations, surface adsorption, and finally, coordination by the polyamine. 2.5 mmol/g of amino-groups in a linear ethylene-amine based organoclay are enough to remove all the lanthanum ions in solution when contacted with containing 0.48 mmol/g clay, i.e. 2600 ppm/clay. 12 coordinating sites are needed for each lanthanum ion. Finally, the organic part of the sorbent solid is highly stable, being unmodified upon many cycles of use. The release step is greatly pH dependent, and the optimised pH is equal to 1. Under these conditions, release efficiencies are always higher than 80 %. Appling multiple steps and intermediate re-basification, very high and reproducible global efficiencies (up to 90 %) are reached.
Minerals, 2020
Metals from electric and electronic waste equipment (WEEE) can be recovered by dissolution with a... more Metals from electric and electronic waste equipment (WEEE) can be recovered by dissolution with acids followed by liquid–liquid extraction. A possible alternative to liquid–liquid extraction is liquid–solid adsorption, where sorbents efficiency is the key factor for process efficiency. In this respect, aim of this paper is the study of the behaviour of two solid sorbents for the recovery of Rare Earths (REs)—in particular, La, Nd, and Y—from scraps of end-of-Life (EOL) electronic equipment. Two solid matrices were considered: a pristine montmorillonite clay and a modified-montmorillonite clay intercalated with a commercial pentaethylen-hexamine. The capture ability of the solids was tested towards single-ion La, Nd, and Y solutions and a multi-element solution containing the three ions. Before and after the uptake step, samples of both the solid and liquid phases were analysed. For both sorbents, at lower metal initial concentrations, the ions were captured in similar amount. At hig...
Archaeometry, 2020
This study presents the results of new research into Etruscan technology for earthen architecture... more This study presents the results of new research into Etruscan technology for earthen architecture as well as ceramic production in the upper Tiber Valley in central Italy, using as a case study the Etruscan settlement of Col di Marzo (Perugia). It determines the compositional differences of the raw material employed as building material and for ceramic production by X‐ray powder diffraction (XRD), thermogravimetric analysis and differential thermal analysis (TG‐DTG), Fourier‐transform infrared analysis (FTIR) and geotechnical analyses. The research also advances the knowledge of ceramic manufacturing technology, with a focus on impasto production, at Col di Marzo between the fifth and mid‐third centuries bce and the surrounding territory on the left bank of the River Tiber. The compositional analysis of building material compared with the ceramics provides answers to questions related to their sourcing and deepens the understanding of the exploitation of natural resources.
XV International Conference on Durability of Building Materials and Components. eBook of Proceedings, 2020
In the framework of Circular Economy policies aimed at reducing the consumption of raw materials,... more In the framework of Circular Economy policies aimed at reducing the consumption of raw materials, shives, as an agricultural by-product of hemp cultivation, have gained a renovated life in the construction sector. Its excellent thermal insulating properties permitted the development of new building materials to be used in various executive technologies. When shives are mixed with a mineral binder such as lime or cement, the mixture is usually referred to as hempcrete. In Italy, the use of hempcrete and the development of new production chains and implementation techniques dates back only to about the last decade, while other European countries have more long-lasting experiences (90s). In order to assess the potential benefits of hempcrete in the construction sector, its environmental performances were evaluated using the LCA methodology, by comparing four non-loadbearing representative walls, one made with hempcrete blocks and the others with more "traditional" materials. This research constitutes a solid basis for the development of future guidelines and/or regulations at national and international level in order to guarantee the maximum diffusion of this type of product. Then, a study has been carried out regarding the functionality of hempcrete blocks in masonry, layered with finishing plaster made of fine hemp shives, to evaluate the in-situ hygrothermal building performance. In particular, measurement methods were developed and analysis were carried out on two houses, one in northern Italy and one in southern Italy, and precisely in Sicily, focusing the study on the performances of the walls subjected to warm Mediterranean climates. Indeed, the literature on masonry behavior in hot Mediterranean climates is much scarcer than in cold climates.
IOP Conference Series: Earth and Environmental Science, 2019
In the Genova hinterland, a traditional rural dwelling has been completely restored with the addi... more In the Genova hinterland, a traditional rural dwelling has been completely restored with the addition of new buildings respecting the landscape and the relationship with the existing vernacular construction. The project, in compliance with all the bio-architecture criteria of intervention associates traditional natural materials such as stone and lime with cutting-edge materials and techniques such as raw earth and hempcrete. Both the recovery and the new buildings have been the subject of meticulous bio-design in terms of material choices and diversification of construction techniques according to the area of intervention and of the local material culture. The original stone walls have been preserved and consolidated with fibre-reinforced lime mortar applied directly on the stone wall after removing the old mortar. Timber beams and wooden floors have been almost completely renovated, but preserving and consolidating wherever possible the original structures. External walls have bee...
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Papers by Giovanni Dotelli