3,567 research outputs found
Floating Photocatalysts as a Sustainable Solution for Water Harvesting in Vulnerable Communities
No full textThe exponential growth of the global population, projected to exceed 9 billion people by 2050, combined with increasing water scarcity driven by climate change, is placing unprecedented pressure on the world's water resources [1]. This issue is even more pronounced in developing countries, where water scarcity is a key factor behind numerous public health crises, during which unsanitary conditions expose both patients and doctors to risks of disease transmission [2].
In this challenging scenario, treating the tons of wastewater generated every day offers a promising solution. By transforming wastewater into a viable alternative water source, this approach addresses both resource scarcity and environmental sustainability. Although various technologies have been developed for water depollution (e.g., filtration, chemical or biological treatments) [3], they generally fail to remove contaminants of emerging concern (CECs) due to their high chemical stability, so developing efficient technologies for wastewater purification is crucial to mitigating water scarcity and ensuring access to safe water for all. In this framework, photocatalysis plays a pivotal role; indeed, the use of sunlight, an extremely powerful and abundant energy source, represents a vital resource in light of the current energy crisis. However, developing photocatalytic materials capable of exploiting the entire solar spectrum for pollutant photodegradation is challenging. Additionally, the most advanced materials reported in the literature are typically used as dispersed powders. Even if working with fine powders offers several benefits (e.g., high dispersion and impressive photoactivity), it also presents critical challenges, such as the difficulty of recovering them from the reaction mixture, which leads to contamination issues and additional costs [4]. For this reason, immobilizing photocatalysts strikes a balance between their advantages and the need for practical application by enhancing stability and enabling easier handling. In this context, floating photocatalysts offer the advantage of maximizing both light utilization and surface aeration, as they can remain at the air-water interface. Their use also reduces post-treatment costs. These foundations inspired the development of the project “Water Decontamination by Sunlight-Driven Floating Photocatalytic Systems” (SUNFLOAT). Within the SUNFLOAT project, various safe, cost-effective, and highly efficient photocatalysts designed to operate under solar irradiation were successfully fabricated and immobilized on different synthetic and natural floating supports [5-6]. The resulting materials were rigorously tested for the photodegradation of various CECs under both simulated and real sunlight conditions. The innovation introduced by the SUNFLOAT project highlights the practical viability of floating photocatalysts under natural solar conditions. The project underscores the effectiveness of these novel materials in harnessing solar energy for sustainable water purification. By proving their functionality under real sunlight, this initiative represents a significant advancement, offering an eco-friendly and scalable solution to improve water quality for remote communities facing water scarcity.
References:
[1]: He, C., Liu, Z., Wu, J., Pan, X., Fang, Z., Li, J., Brett, A.B., Nat. Commun.12, 4667 (2021).
[2]: https://www.cdc.gov
[3] Galloni, M.G., Ferrara, E., Falletta, E., Bianchi, C.L., Catalyst 12(8), 923, (2022).
[4] Djellabi, R., Giannantonio, R., Falletta, E., Bianchi, C.L., Curr. Opin. Chem. Eng.33, 100696 (2021).
[5] Galloni, M.G., Falletta, E., Mahdi, M., Giordana, A., Cerrato, G., Boffito, D.C., Bianchi, C.L., Adv. Sus. Syst. 2300565 (2024).
[6] Galloni, M.G., Nikonova, V., Cerrato, G., Giordana, A., Pleva, P., Humpolicek, P., Falletta, E., Bianchi, C.L., J. Environ. Man., 369, 122365, (2024)
Floating photocatalysts as an innovative solar-powered technology for wastewater treatment: leveraging sustainability to support vulnerable communities
No full textNowadays, preserving freshwater is crucial, especially in developing countries, where the risk of disease transmission is elevated. (Galloni et al., 2024) Ibuprofen (IBU) and diclofenac (DCF) are nonsteroidal anti-inflammatory drugs (NSAIDs), whose concentration in surface waters is increasing due to the rapid growth/aging of world population. (Galloni et al., 2024) So, the possible purification/reuse of wastewater represents a challenging task. Among the strategies to abate NSAIDs, photocatalysis exploits solar energy - a free and clean resource. Its potential is to significantly aid the development of regions frequently impoverished and densely populated, demonstrating a practical application of renewable energy in enhancing global water quality. However, the most part of photocatalytic systems hides a practical limitation, i.e., the difficult recovery as powders from the reaction mixture, causing contamination issues and additional costs. In this context, sustainable floating photocatalysts are viable alternatives to be used: their floatability on the air-water interface maximizes both light absorption and surface aeration, enhancing pollutant removal efficiency and reducing post-treatment costs. However, finding a simple, cheap, and universally accessible method for applying photocatalysis in water purification, especially in communities with limited access to clean water, remains an ongoing challenge. Herein, we propose the development of an innovative sunlight-driven device composed by bismuth oxybromide (BiOBr) grown on a naturally derived material (Lightweight Expanded Clay Aggregate, LECA), to clean surface waters under natural solar irradiation. Photodegradation of IBU and DCF was investigated in laboratory- and real-scale experiments. The BiOBr/LECA photocatalyst fully degrades DCF, whereas restricted abatement of IBU is observed (Figure) (Galloni et al., 2024). The identification of specific transformation products (TPs) during the degradation reveals that this behaviour is related to the different structures of drugs. Reusability tests demonstrate the high stability of the floating composite. These encouraging results pave the path toward a promising novel and sustainable paradigm for water remediation
Solar-powered solutions: floating photocatalysts for sustainable water purification in a resource-challenged world
No full textThe exponential growth of the global population, projected to exceed 9 billion people by 2050, combined with increasing water scarcity driven by climate change, is placing unprecedented pressure on the world's water resources [1]. This issue is even more pronounced in developing countries, where water scarcity is a key factor behind numerous public health crises, during which unsanitary conditions expose both patients and doctors to risks of disease transmission [2].
In this challenging scenario, treating the tons of wastewater generated every day offers a promising solution. By transforming wastewater into a viable alternative water source, this approach addresses both resource scarcity and environmental sustainability. Although various technologies have been developed for water depollution (e.g., filtration, chemical or biological treatments) [3], they generally fail to remove contaminants of emerging concern (CECs) due to their high chemical stability, so developing efficient technologies for wastewater purification is crucial to mitigating water scarcity and ensuring access to safe water for all. In this framework, photocatalysis plays a pivotal role; indeed, the use of sunlight, an extremely powerful and abundant energy source, represents a vital resource in light of the current energy crisis. However, developing photocatalytic materials capable of exploiting the entire solar spectrum for pollutant photodegradation is challenging. Additionally, the most advanced materials reported in the literature are typically used as dispersed powders. Even if working with fine powders offers several benefits (e.g., high dispersion and impressive photoactivity), it also presents critical challenges, such as the difficulty of recovering them from the reaction mixture, which leads to contamination issues and additional costs [4]. For this reason, immobilizing photocatalysts strikes a balance between their advantages and the need for practical application by enhancing stability and enabling easier handling. In this context, floating photocatalysts offer the advantage of maximizing both light utilization and surface aeration, as they can remain at the air-water interface. Their use also reduces post-treatment costs. These foundations inspired the development of the project “Water Decontamination by Sunlight-Driven Floating Photocatalytic Systems” (SUNFLOAT). Within the SUNFLOAT project, various safe, cost-effective, and highly efficient photocatalysts designed to operate under solar irradiation were successfully fabricated and immobilized on different synthetic and natural floating supports [5-6]. The resulting materials were rigorously tested for the photodegradation of various CECs under both simulated and real sunlight conditions. The innovation introduced by the SUNFLOAT project highlights the practical viability of floating photocatalysts under natural solar conditions. The project underscores the effectiveness of these novel materials in harnessing solar energy for sustainable water purification. By proving their functionality under real sunlight, this initiative represents a significant advancement, offering an eco-friendly and scalable solution to improve water quality for remote ommunities facing water scarcity.
References:
[1]: He, C., Liu, Z., Wu, J., Pan, X., Fang, Z., Li, J., Brett, A.B., Nat. Commun.12, 4667 (2021).
[2]: https://www.cdc.gov
[3]: Galloni, M.G., Ferrara, E., Falletta, E., Bianchi, C.L., Catalyst 12(8), 923, (2022)
[4]: Djellabi, R., Giannantonio, R., Falletta, E., Bianchi, C.L., Curr. Opin. Chem. Eng.33, 100696 (2021)
[5]: Galloni, M.G., Falletta, E., Mahdi, M., Giordana, A., Cerrato, G., Boffito, D.C., Bianchi, C.L., Adv. Sus. Syst. 2300565 (2024),
[6] Galloni, M.G., Nikonova, V., Cerrato, G., Giordana, A., Pleva, P., Humpolicek, P., Falletta, E., Bianchi, C.L., J. Environ. Man., 369, 122365, (2024
Floral rewards and pollinator performance in the generalist Gentiana lutea L.
No full textWe studied the pollination ecology of G. lutea L., an incompletely compatible species (Kozuharova 1998, Rossi 2012), assessing the spectrum of visitors and their pollinating role in relation to floral rewards, and specifically to nectar quality. Floral visitors behaviour and frequency were recorded in three natural populations of G. lutea belonging to subspecies lutea, vardjanii and symphyandra, during two consecutive years. We analysed insect pollen load and calculated an index of Pollinator Importance based on visitor frequency, fidelity and behavior (Galloni et al. 2008, Gibson et al. 2006). The occurrence of pollen limitation on reproductive success and nectar chromatographic analysis were performed on each studied population. The spectrum of pollinators shows a generalized system, since four orders of insects were observed, confirming previous results by Kozuharova (1999). However, not all pollinators play the same role: insects with sedentary activity would mainly contribute to geitonogamy while a dynamic behaviour would mainly increase out-crossing. Bumblebees, common wasps, bees, halictid bees and syrphid flies are example of taxa with a dynamic behaviour; ants are regarded as nectar thieves. Flies and Coleoptera show a sedentary activity. The best pollinator performance was found in subsp. symphyandra population, followed by subsp. lutea (where sedentary pollinators show a limited impact) and subsp. vardjanii, where the importance of sedentary pollinators exceeds that of dynamics. In this population pollen limitation was observed in both study years, while in the other ones in just one year. Reduced seed set can result as a consequence of low pollen quantity or quality. The high pollinator activity observed suggests that pollen limitation could be mainly explained by the quality of pollen (cross vs. self). Moreover multi-flowering species, characterized by a scarce level of compatibility may be particularly prone to pollen limitation by quality, primarily due to stigma clogging. Chromatographic analysis reveals that G. lutea nectar is rich in hexose and shows a significant presence of B-alanine and proline. From field surveys we observed two different behaviours of bumblebees: individuals collecting pollen showed a dynamic behaviour, while individuals foraging for nectar showed a tendency to become sluggish and sedentary. Pollen vectors are critical for the successful reproduction of this mainly xenogamous species, which moreover shows a very high inbreeding depression (Rossi 2012). Among pollinators is possible to discriminate “the good” (dynamic) – “the bad” (sedentary) – and “the null” (no contribution to pollination). Pollen limitation seems to be related with the degree of geitonogamy, enhanced by the “bad” pollinators. Pollinator behaviour seems to be affected by nectar quality (see also Nocentini et al. 2012). In particular, the role of amino acids needs further investigations, with special regard to B-alanine which is a non protein amino acid
Innovative eco-friendly materials for wastewater remediation: how photocatalysis embraces the sustainable future
No full textEfforts to optimize pollution control technologies have been recently intensified to minimize harmful emissions in water, aligning with stringent legislative requirements [1]. Heterogeneous photocatalysis has emerged as a sustainable approach to mitigate toxic pollutants in the environment. However, its effectiveness is limited, and its enhancement remains a challenge [2]. The use of nano-sized materials, although common, raises concerns about nanotoxicity. The ideal photocatalyst should possess activity, selectivity, stability, non-toxicity, cheapness, and easy handling. Achieving all these requirements is a difficult task.
In our recent work, we have focused on developing advanced TiO2-free materials for water remediation. We have studied photocatalytic active phases immobilized on eco-friendly supports able to eliminate organic pollutants from aqueous solutions. The economic advantage is the easy material recovery, and the utilization of floating supports enhances photocatalytic performances due to the large, exposed surface area and efficient aeration [3].
We have performed characterizations on morphology, structure, and metal speciation at the photocatalyst surface, elucidating potential and limitations of each sustainable support in the respective applications and providing critical insights into photocatalytic performances.
[1] Guerra, F.D. et al., Molecules 2018, 23(7), 1760; [2] Djellabi, R. et al., Chem. Eng. 2021, 1:100696; [3] Galloni, M.G. et al., Catalysts 2022, 12(8), 923
The virtuous life-cycle of hydroxyapatite : from removal of heavy metals in polluted wastewaters to new eco-friendly catalysts for air- quality protection
No full textIn the last decades, the development and improvement of ecofriendly materials for pollution control have been object of intensive research efforts devoted to comply with the ever more stringent legislative constraints for minimizing harmful emission in water and air.
Among all the calcium phosphate materials, calcium hydroxypatite (HAP, Ca10(PO4)6(OH)2) is a versatile material that has gained attention in many fields of applied science because of its typical features (e.g. high chemical and thermal stability, extremely low solubility, low cost, large availability and easy synthesis, and ion exchange capability).
Current studies of our research group have proved that this material is able to permanently immobilize polluting hazardous metallic cations (e.g. Cu, Pb, Cr (1)) present in wastewaters with promising yield of removal, if compared with some others adsorbents.
HAP has also found a role in catalysis because of its easy functionalization (2): several metal species of catalytic interest (e.g. Cu, Fe, Mn) can be deposited on its surface with uniform dispersion of metallic centers thanks to the ion exchange ability offered by its structure. The metal obtained HAP samples possess a double functionality, the amphoteric properties, typical of the bare HAP and the electron transfer ability of the metal centers, that are promising properties that can be exploited in catalysis.
In the view of a more sustainable interaction between environment and industry, we are studying the possibility to employ HAP in a so called “virtuous life-cycle” (Fig.1), as sorbent, at first, for removing heavy metals from polluted wastewaters, and then, as metallic catalyst with the possibility to finally recycle both the metallic species and the bare HAP.
In particular, the reuse and valorization of the metal-loaded HAP materials obtained by the first step of de-metallation of wastewaters, allow giving a second life to these materials as catalysts in environmental processes for the abatement of harmful gaseous emissions (e.g. de-NOx, de-VOCs, NH3-SCO, etc.) (3,4).
In this context, the HAP acts as a bridge linking water and air remediation in a fruitful circular process.
This is an interesting example of sustainable process and its realization represents an appealing challenge
Giovanni Galloni: Metodo e insegnamento del diritto agrario
No full textGiovanni Galloni ha sempre unito la sua sincera passione politica con la costanza dell’impegno del giurista. Lo ha fatto, da studioso e, sopra
tutto, da docente, mettendo in campo una pregiudiziale di fondo per le norme scritte: le fonti tradizionali della teoria normativa, che non esauriscono
la comprensione dei fatti – dei rapporti di forza, dell’etica sociale, dell’evoluzione economica – e sono matrice autentica di produzione del diritto.Giovanni Galloni has always combined his sincere political passion with the unwavering commitment of a jurist. He did so, as a scholar and, above all, as a teacher, putting in place a basic preliminary ruling for written norms: the traditional sources of normative theory, which do not exhaust the understanding of facts – of power relations, social ethics, economic evolution – and are the authentic matrix of law making
Plant-Pollinator Integrated CONservation approach: a demonstrative proposal (PP-ICON)
No full textProject background
Some 90% of flowering plant species profit from animal pollination for their reproduction. Pollination systems are under increasing threat from human activities, including fragmentation of habitats, changes in land use and modernisation of agricultural practices, such as increased use of pesticides and herbicides.
Europe’s natural populations of the rare plant burningbush (Dictamnus albus) are declining because a scarcity of pollination services. Moreover, suitable habitats (woodland fringes and clearings) for the plant are also becoming rare because of land-use changes as result of the abandonment of traditional agro-forestry activities.
Wild pollinators are facing a widespread decline, brought about by limatic changes, soil use changes, habitat fragmentation and pollution, which together lead to a scarcity of floral resources and nesting sites.
Project objectives
The main objectives of this LIFE Biodiversity project are to ensure the survival of an isolated population of burning-bush plants and to restore the community of Dictamnus albus natural pollinators in a Bologna
province regional park. Wood management will be carried out, halting forest closure through selective shrub clearings in two sites of 16 ha each. The population of insect pollinators will be increased by providing nesting and egg-laying sites, reintroducing new colonies of the main pollinators and reinforcing populations of other nectariferous plant species in the area.
Expected results
• The actual population of Dictamnus albus is expected to be reinforced, as result of increased natural maternal fertility and reproductive effort (more flowering individuals, higher seed production, more seedlings);
• The overall diversity and abundance of pollinators in the project area will be increased, with benefits not only for the target species, but also for the entire ecosystem;
• The general public will be informed about the project primarily by means of information panels, activities for children and workshops that will take place at the Botanical Garden of Bologna and at seminars across Europe. These dissemination activities should increase awareness about the importance of plantpollinator interactions for plant conservation and ecosystem health;
• Compensation agreements with landowners are foreseen, and particular attention will be given to public and stakeholder awareness to promote pollinator- friendly practices
DESIGN AND EXPERIMENTAL ANALYSIS OF A PROTOTYPE WATERJET FACILITY FOR CATHODE RAY TUBE CUTTING: EVIDENCE FROM A CASE STUDY
No full textCathode Ray Tubes (CRTs) adopted in TV sets and computer monitors represent a consistent portion of Waste Electrical and Electronic Equipment (WEEE). In comparison with the recycling of WEEE such as refrigerators or washing machines, the recovery process for CRT containing devices is very difficult. CRTs are composed of four types of glass (panel, funnel, neck and frit seal) with different compositions. Furthermore, dangerous substances are contained within (i.e. lead, barium, strontium and fluorescent dust). Hence, the need to define robust processes for the design and implementation of efficient facilities for CRT cutting arises. This work describes steps guiding the design and the experimental optimal setting of a prototype facility for water-jet cutting of CRTs, in order to obtain recyclable high quality glass. Initially, a version of the cutting facility with manual movement of the cutting tool is set, in order to evaluate expectable cutting results. Subsequently, a detailed setting of automated movement of the cutting tool is carried out, in order to improve the quality of obtainable glass. As a consequence, a water-jet cutting facility which guarantees the cutting of high quality CRTs is finally set and a prototype is implemented
Polimorfismo fiorale e incompatibilità: gli studi darwiniani sull'eterostilia
No full textDescrizione delle osservazioni botaniche e degli esperimenti effettuati da Charles Darwin per spiegare (da un punto di vista evolutivo) il fenomeno del polimorfismo fiorale, con particolare rifermento agli studi su Primula veris e Lythrum salicaria
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