172,470 research outputs found
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
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
Rational design and optimization of eco-friendly easily recoverable materials for olive mill wastewater treatment
No full textOlive oil production, one of Europe's most flourishing agricultural industries, generates olive oil and undesired products, i.e., pomace and olive mill wastewaters (OMWW). These latter are composed of ca. 80-83 wt.% water, 2 wt.% inorganic matter, and ca. 15-18 wt.% organic compounds (mainly polyphenols, phenols, and tannins). In this context, they require proper disposal treatments because of their complex composition.
In this view, developing efficient sustainable strategies is fundamental [1]. Among all the possibilities, photocatalysis is emerged due to its efficiency, high sustainability, and potential for integration into water purification systems. It can reduce polyphenols and reach high mineralization levels, thus being able to reintroduce water into the environment. Here, a captivating challenge is the rational design of efficient photocatalytic systems with wide light response able to tackle the new challenges in energy, economy, and environmental sustainability of industrial processes [1]. An ideal photocatalyst should be: i) active which means to be able to use sunlight energy to catalyse a chemical reaction; ii) selective, i.e., promoting the formation of desired products; iii) it should be characterized by good stability or durability and regeneration capability. According to these premises, further requirements are needed to obtain an ideal eco-friendly photocatalyst. An environmentally benign photocatalyst should also be easily handled and managed, from its creation to its disposal, non-toxic, biocompatible, and bioavailable [2]. This means that it should be obtained by easy and cheap preparation procedures from common, non-toxic, and safe precursors, or alternatively be extracted by natural sources, or better, biowastes, opening the possibility to recycle and consequently valorise materials at the end-of-life. Eventually, after its use, it should be discarded without causing adverse effects to the environment and human health, or, if possible, be exploited for other applications.
In this work, we present our results related to the rational design of advanced, easily recoverable materials based on bismuth oxybromide (BiOBr) supported onto sustainable materials (alginate, Fe3O4-alginate spheres) for the treatment of simple matrixes containing model polyphenols representatives of the OMWW fraction.
A critical insight into the potentialities and/or shortcomings related to the studies of advanced materials will be discussed. A targeted physico-chemical characterization and a proper evaluation of the abatement of different polyphenols in the dark and after exposure to solar or visible light irradiation will be described.
The encouraging obtained results deserve a deeper study, but already open the view towards the future use of these systems in real applications, particularly in applying sustainability principles to industrial processes.
References
[1] Galloni, M.G.; Ferrara, E.; Falletta, E.; Bianchi, C. L. Catalysts 2022, 12(8), 923. [2] Anastas, P.T.; Kirchhoff, M.M.; Williamson, T.C. Applied Catalysis A: Gen. 2001, 221, 3-13
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)
Innovative eco-friendly materials for environmental remediation: when photocatalysis meets sustainability
No full textEfforts to optimize pollution control technologies have been recently intensified to minimize harmful emissions in water and air, 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 and air remediation. Firstly, we have studied catalysts 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]. Secondly, we have studied silver-modified strontium titanates for degrading nitrogen oxides. Here, our challenge is to develop efficient materials stable at high temperatures [4] and active in the visible light region, harvesting sunlight or LED lighting in the interior.
We have performed characterizations on morphology, structure, and metal speciation at the photocatalyst surface, elucidating potential and limitations of each material 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; [4] Djellabi, R. et al., Haz. Mat. 2022, 421, 126792
"Sento il tuo dolore": la capacità di esperire e condividere sensazioni ed emozioni alla base di un nuovo concetto di mente neurobiologicamente fondato
No full textSolar-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
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