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1.
Proc Natl Acad Sci U S A ; 121(9): e2317435121, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38377211

RESUMEN

Creating efficient catalysts for simultaneous H2O2 generation and pollutant degradation is vital. Piezocatalytic H2O2 synthesis offers a promising alternative to traditional methods but faces challenges like sacrificial reagents, harsh conditions, and low activity. In this study, we introduce a cobalt-loaded ZnO (CZO) piezocatalyst that efficiently generates H2O2 from H2O and O2 under ultrasonic (US) treatment in ambient aqueous conditions. The catalyst demonstrates exceptional performance with ~50.9% TOC removal of phenol and in situ generation of 1.3 mM H2O2, significantly outperforming pure ZnO. Notably, the CZO piezocatalyst maintains its H2O2 generation capability even after multiple cycles, showing continuous improvement (from 1.3 mM to 1.8 mM). This is attributed to the piezoelectric electrons promoting the generation of dynamic defects under US conditions, which in turn promotes the adsorption and activation of oxygen, thereby facilitating efficient H2O2 production, as confirmed by EPR spectrometry, XPS analysis, and DFT calculations. Moreover, the CZO piezocatalysts maintain outstanding performance in pollutant degradation and H2O2 production even after long periods of inactivity, and the deactivated catalyst due to metal ion dissolution could be rejuvenated by pH adjustment, offering a sustainable solution for wastewater purification.

2.
Nano Lett ; 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39365030

RESUMEN

Biodegradable shape-memory polymers derived from protein substrates are attractive alternatives with strong potential for valorization, although their reconstruction remains a challenge due to the poor processability and inherent instability. Herein, based on Maillard reaction and immobilization, a feather keratin fibrous adsorbent featuring dual-response shape-memory is fabricated by co-spinning with pullulan, heating, and air-assisted spraying ZIF-8-NH2. Maillard reaction between the amino group of keratin and the carbonyl group of pullulan improves the mechanics and thermal performance of the adsorbent. ZIF-8-NH2 immobilization endows the adsorbent with outstanding multipollutant removal efficiency (over 90%), water stability, and photocatalytic degradation and sterilization performance. Furthermore, the adsorbent can be folded to 1/12 of its original size to save space for transportation and allow for rapid on-demand unfolding (12 s) upon exposure to water and ultraviolet irradiation to facilitate the adsorption and photocatalytic activity with a larger water contact area. This research provides new insight for further applications of keratin-based materials with rapid shape-memory features.

3.
BMC Plant Biol ; 24(1): 855, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39266960

RESUMEN

Management of molasses-based wastewater generated in yeast and sugar industries is a major environmental concern due to its high chemical oxygen demand and other recalcitrant substances. Several strategies have been used to reduce the inland discharge of wastewater but the results are not satisfactory due to high operating cost. However, reuse of molasses-based wastewater irrigation in agriculture has been a major interest nowadays to reduce the freshwater consumption. Thus, it is crucial to monitor the impacts of molasses-based waste water irrigation on growth, metabolism, yield and nutritional quality of crops for safer consumer's health. In present study, carrot seeds of a local cultivar (T-29) were germinated on filter paper in Petri dishes under controlled conditions. The germinated seeds were then transplanted into pots and irrigated with three different treatments normal water (T0), diluted molasses-based wastewater (T1), and untreated molasses-based wastewater (T2), in six replicates. Results revealed that carrot irrigated with untreated molasses-based waste water had exhibited significant reductions in growth, yield, physiology, metabolism, and nutritional contents. Additionally, accumulation of Cd and Pb contents in carrot roots irrigated with untreated molasses-based waste water exceed the permissible limits suggested by WHO and their consumption may cause health risks. While, diluted molasses-based waste water irrigation positively enhanced the growth, yield of carrot plants without affecting the nutritional quality. This strategy is cost effective, appeared as most appropriate alternative mean to reduce the freshwater consumption in water deficit regions of the world.


Asunto(s)
Riego Agrícola , Daucus carota , Melaza , Aguas Residuales , Daucus carota/crecimiento & desarrollo , Daucus carota/metabolismo , Aguas Residuales/química , Riego Agrícola/métodos , Valor Nutritivo
4.
Small ; 20(26): e2306943, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38239086

RESUMEN

The growing consumption of drugs of abuse together with the inefficiency of the current wastewater treatment plants toward their presence has resulted in an emergent class of pollutants. Thus, the development of alternative approaches to remediate this environmental threat is urgently needed. Microrobots, combining autonomous motion with great tunability for the development of specific tasks, have turned into promising candidates to take on the challenge. Here, hybrid urchin-like hematite (α-Fe2O3) microparticles carrying magnetite (Fe3O4) nanoparticles and surface functionalization with organic ß-cyclodextrin (CD) molecules are prepared with the aim of on-the-fly encapsulation of illicit drugs into the linked CD cavities of moving microrobots. The resulting mag-CD microrobots are tested against methamphetamine (MA), proving their ability for the removal of this psychoactive substance. A dramatically enhanced capture of MA from water with active magnetically powered microrobots when compared with static passive CD-modified particles is demonstrated. This work shows the advantages of enhanced mass transfer provided by the externally controlled magnetic navigation in microrobots that together with the versatility of their design is an efficient strategy to clean polluted waters.


Asunto(s)
Ciclodextrinas , Metanfetamina , Contaminantes Químicos del Agua , Metanfetamina/química , Ciclodextrinas/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Magnetismo , Robótica , Purificación del Agua/métodos , Compuestos Férricos/química
5.
Environ Res ; 245: 117999, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38154567

RESUMEN

The waste management and water purification are daunting environmental challenges. Biochar, a carbonaceous material prepared from diverse organic waste (agricultural, household residues and municipal sewage sludge) has garnered substantial attention due to its excellent attributes, including carbon content, cation exchange efficacy, ample specific surface area, and structural robustness. Thus, the present review comprehensively analyzes bio waste-derived biochar with a particular emphasis on water remediation applications. This article primarily delves into various strategies for modifying biochar, elucidating the underlying mechanisms behind these modifications and their potential for bolstering pollutant removal efficiency. Furthermore, it addresses the impact of functionalization on both biochar stability and cost for commercialization. Lastly, the article outlines key developments, SWOT analysis, and future prospects, offering insights into the practical execution of biochar applications at a larger scale. Therefore, this article paves the way for future research to deepen the understanding of modified biochar with mechanisms for exploring water remediation applications in a more sustainable manner.


Asunto(s)
Contaminantes Ambientales , Restauración y Remediación Ambiental , Administración de Residuos , Carbón Orgánico , Aguas del Alcantarillado , Suelo
6.
Environ Res ; 246: 118001, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38145730

RESUMEN

In recent years, extensive research endeavors are being undertaken for synthesis of an efficient, economic and eco-friendly cerium oxide nanoparticles (CeO2 NPs) using plant extract mediated greener approach. A number of medicinal plants and their specific parts (flowers, bark, seeds, fruits, seeds and leaves) have been found to be capable of synthesizing CeO2 NPs. The specific key phytochemical constituents of plants such as alkaloids, terpenoids, phenolic acids, flavones and tannins can play significant role as a reducing, stabilizing and capping agents in the synthesis of CeO2 NPs from their respective precursor solution of metal ions. The CeO2 NPs are frequently using in diverse fields of science and technology including photocatalytic degradation of dyes, antibiotics as well as antimicrobial applications. In this review, the mechanism behind the green synthesis CeO2 NPs using plant entities are summarized along with discussion of analytical results from characterization techniques. An overview of CeO2 NPs for water remediation application via photocatalytic degradation of dyes and antibiotics are discussed. In addition, the mechanisms of antimicrobial efficacy of CeO2 NPs and current challenges for their sustainable application at large scale in real environmental conditions are discussed.


Asunto(s)
Antiinfecciosos , Cerio , Nanopartículas del Metal , Nanopartículas , Antibacterianos/química , Colorantes , Nanopartículas/química , Cerio/química , Plantas , Nanopartículas del Metal/química
7.
Int J Phytoremediation ; : 1-14, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39138934

RESUMEN

Herbicide contamination in aquatic systems has become a global concern due to their long- term persistence, accumulation and health risks to humans. Paraquat, a widely used and cost-effective nonselective herbicide, is frequently applied in agricultural fields for pest control. Consequently, the removal of paraquat from contaminated water is crucial. This research presents a sustainable and environmentally benign method for paraquat removal from aqueous system by integrating wetland plants (Eichhornia crassipes) with biochar derived from melamine-modified palm kernel shells. The prepared biochar was characterized by using various analytical techniques. The effectiveness of biochar in enhancing phytoremediation was evaluated through a series of experiments, showing significant paraquat removal efficiencies of 99.7, 98.3, and 82.8% at different paraquat concentrations 50, 100, and 150 mg L-1, respectively. Additionally, present study examined the impact of biochar on the growth of E. crassipes, highlighting its potential to reduce the toxic effects of paraquat even present at higher concentrations. The paraquat removal mechanism was elucidated, focusing on the synergistic role of biochar adsorption and phytoremediation capability of E. crassipes. This innovative approach is an effective, feasible, sustainable and eco-friendly technique that can contribute to the development of advanced and affordable water remediation processes for widespread application.


The novelty of this study lies in the implementation of combined approach by phytoremediation with biochar modified with melamine. This study highlighted synergistic integration of two concurrent systems. The biochar generated from waste palm kernel shells played a pivotal role in facilitating the plants' survival and resilience against the paraquat toxicity, rather than succumbing to its deleterious effects. This research delineates a robust methodology for the elimination of emerging pollutants, offering researchers a platform to make pioneering advancements in this scientific field for sustainable future.

8.
Nano Lett ; 23(23): 11243-11251, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38011156

RESUMEN

Self-propelled nanomotors represent a promising class of adaptable and versatile technologies with broad applications in the realms of biomedicine and environmental remediation. Herein, we report a biocatalytic nanomotor based on a covalent-organic framework (COF) that demonstrates intelligent and switchable motion triggered by a blue-to-red light switch. Consequently, when exposed to blue light, the nanomotor significantly enhances the removal of contaminants in aqueous solutions due to its elevated mobility. Conversely, it effectively deactivates its motion and contaminant removal upon exposure to red light. This study explores the heterogeneous assembly strategy of the COF-based nanomotor and its light-controlled propulsion performance and provides a novel strategy for the regulation of movement, offering valuable insights for the design and practical applications of nanomotors.

9.
J Environ Manage ; 353: 120114, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38280250

RESUMEN

The laccase mediator system (LMS) with a broad substrate range has attracted much attention as an efficient approach for water remediation. However, the practical application of LMS is limited due to their high solubility, poor stability and low reusability. Herein, the bimetallic Cu/ZIFs encapsulated laccase was in-situ grown in poly(vinyl alcohol) (PVA) polymer matrix. The PVA-Lac@Cu/ZIFs hydrogel was formed via one freeze-thawing cycle, and its catalytic stability was significantly improved. The mediator was further co-immobilized on the hydrogel, and this hierarchically co-immobilized ABTS/PVA-Lac@Cu/ZIFs hydrogel could avoid the continuous oxidation reaction between laccase and redox mediators. The co-immobilized LMS biocatalyst was used to degrade malachite green (MG), and the degradation rate was up to 100 % within 4 h. More importantly, the LMS could be recycled synchronously from the dye solutions and reused to degrade MG multiple times. The degradation rate remained above 69.4 % after five cycles. Furthermore, the intermediate products were detected via liquid chromatography-mass spectrometry, and the potential degradation pathways were proposed. This study demonstrated the significant potential of utilizing the MOF nanocrystals and hydrogel as a carrier for co-immobilized LMS, and the effective reuse of both laccase and mediator was promising for laccase application in wastewater treatment.


Asunto(s)
Enzimas Inmovilizadas , Lacasa , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Lacasa/química , Lacasa/metabolismo , Hidrogeles/química , Colorantes de Rosanilina/química
10.
J Environ Manage ; 370: 122714, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39383756

RESUMEN

This work aims to apply carbon quantum dots (CQDs) from agriculture cellulosic waste (agro wastes), produced via an economically and eco-friendly single-step method, to be used into cellulose acetate composite microfibrous membranes as an innovative solution specifically designed to adsorb methylene blue (MB) and other cationic dyes that are present in various water effluents. Batch adsorption tests were conducted, with variations in contact time (1-24 h), initial MB concentration (25-300 ppm), and adsorbent doses (1-20 g/L). The maximum adsorption capacity of the membrane was 198 mg/g with an initial concentration of 300 ppm at 298 K. Thermodynamic parameters showed that the process is endothermic. Equilibrium experimental data for MB adsorption onto electrospun adsorbent were fitted using different isothermal models, with the Freundlich model showing the best fit. The pseudo-second-order model accurately described the kinetic data with high reliability (R2 > 0.99), and the calculated adsorption capacity was very close to the experimental data. N-CQDs loaded membranes were also tested for removing methyl violet and rhodamine B, demonstrating remarkably high dye removal efficiency. The underlying adsorption mechanism was also reported. Finally, it is worth mentioning that composite adsorbents can be efficiently applied to actual industrial cases because of the possibility of reusing them, opening the route to the fabrication of novel and highly performant adsorbents. These findings underscore N-CQDs' effectiveness in enhancing pollutant removal efficiency from wastewater, highlighting their environmental benefits and promoting a more sustainable approach to water treatment. Therefore, the prepared adsorbent, showing excellent adsorption performance, places them among adsorbents for practical applications in wastewater purification.

11.
J Environ Manage ; 366: 121879, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39043086

RESUMEN

Environmental electrochemistry and water resource recovery are covered in this review. The study discusses the growing field's scientific basis, methods, and applications, focusing on innovative remediation tactics. Environmental electrochemistry may solve water pollution and extract resources. Electrochemical methods may effectively destroy or convert pollutants. This method targets heavy metals, organic compounds, and emerging water contaminants such as pharmaceuticals and microplastics, making it versatile. Environmental electrochemistry and resource recovery synergize to boost efficiency and sustainability. Innovative electrochemical methods can extract or synthesise metals, nutrients, and energy from wastewater streams, decreasing treatment costs and environmental effect. The study discusses electrocoagulation, electrooxidation, and electrochemical advanced oxidation processes and their mechanics and performance. Additionally, it discusses current electrode materials, reactor designs, and process optimisation tactics to improve efficiency and scalability. Resource recovery in electrochemical remediation methods is also examined for economic and environmental feasibility. Through critical examination of case studies and techno-economic evaluations, it explains the pros and cons of scaling up these integrated techniques. This study covers environmental electrochemistry and resource recovery's fundamental foundations, technology advances, and sustainable water management consequences.


Asunto(s)
Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/química , Aguas Residuales/química , Técnicas Electroquímicas , Metales Pesados/química
12.
J Environ Manage ; 356: 120566, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38520854

RESUMEN

Quiescent batch experiments were conducted to evaluate the influences of Cl-, F-, HCO3-, HPO42-, and SO42- on the reactivity of metallic iron (Fe0) for water remediation using the methylene blue (MB) method. Strong discoloration of MB indicates high availability of solid iron corrosion products (FeCPs). Tap water was used as an operational reference. Experiments were carried out in graduated test tubes (22 mL) for up to 45 d, using 0.1 g of Fe0 and 0.5 g of sand. Operational parameters investigated were (i) equilibration time (0-45 d), (ii) 4 different types of Fe0, (iii) anion concentration (10 values), and (iv) use of MB and Orange II (O-II). The degree of dye discoloration, the pH, and the iron concentration were monitored in each system. Relative to the reference system, HCO3- enhanced the extent of MB discoloration, while Cl-, F-, HPO42-, and SO42- inhibited it. A different behavior was observed for O-II discoloration: in particular, HCO3- inhibited O-II discoloration. The increased MB discoloration in the HCO3- system was justified by considering the availability of FeCPs as contaminant scavengers, pH increase, and contact time. The addition of any other anion initially delays the availability of FeCPs. Conflicting results in the literature can be attributed to the use of inappropriate experimental conditions. The results indicate that the application of Fe0-based systems for water remediation is a highly site-specific issue which has to include the anion chemistry of the water.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Hierro , Agua , Aniones , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos
13.
Molecules ; 29(12)2024 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-38930923

RESUMEN

Endophytic microorganisms contribute significantly to water bioremediation by enhancing pollutant degradation and supporting aquatic plant health and resilience by releasing bioactive compounds and enzymes. These microorganisms inhabit plant tissues without causing disease or any noticeable symptoms. Endophytes effectively aid in eliminating contaminants from water systems. Nanoparticles serve as potent enhancers in bioremediation processes, augmenting the efficiency of pollutant degradation by increasing surface area and bioavailability, thereby improving the efficacy and rate of remediation. Their controlled nutrient release and ability to stabilize endophytic colonization further contribute to the enhanced and sustainable elimination of contaminated environments. The synergistic effect of endophytes and nanoparticles in water remediation has been widely explored in recent studies, revealing compelling outcomes. Water pollution poses significant threats to human health, ecosystems, and economies; hence, the sixth global goal of the Sustainable Development Agenda 2030 of the United Nations aims to ensure the availability and sustainable management of water resources, recognizing their crucial importance for current and future generations. Conventional methods for addressing water pollution exhibit several limitations, including high costs, energy-intensive processes, the production of hazardous by-products, and insufficient effectiveness in mitigating emerging pollutants such as pharmaceuticals and microplastics. Noticeably, there is an inability to effectively remove various types of pollutants, thus resulting in incomplete purification cycles. Nanoparticle-enhanced water bioremediation offers an innovative, eco-friendly alternative for degrading contaminants. A growing body of research has shown that integrating endophytic microorganisms with nanoparticles for water bioremediation is a potent and viable alternative. This review examines the potential of using endophytic microorganisms and nanoparticles to enhance water remediation, exploring their combined effects and applications in water purification. The paper also provides an overview of synthetic methods for producing endophyte-nanoparticle composites to optimize their remediation capabilities in aqueous environments. The final section of the review highlights the constraints related to integrating endophytes with nanoparticles.


Asunto(s)
Biodegradación Ambiental , Endófitos , Nanopartículas , Nanopartículas/química , Endófitos/metabolismo , Purificación del Agua/métodos , Contaminantes Químicos del Agua , Humanos
14.
Molecules ; 29(16)2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39202946

RESUMEN

This study demonstrated the synthesis of Fe2MnO4 modified by citric acid, a biodegradable acid, using a simple co-precipitation method. Characterization was performed using qualitative analysis techniques such as Fourier-transformed infrared spectroscopy, scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy, X-ray diffraction, selected-area electron diffraction, N2 adsorption-desorption, and zero-point charge. The prepared nanoparticles had a rough and porous surface, and contained oxygenous (-OH, -COOH, etc.) functional groups. The specific surface area and average pore size distribution were 83 m2/g and 5.17 nm, respectively. Net zero charge on the surface of the prepared nanoparticles was observed at pH 7.5. The prepared nanoparticles were used as an adsorbent to remove methylene blue dye from water under various conditions. Using small amounts of the adsorbent (2.0 g/L), even a high concentration of MB dye (60 mg/L) could be reduced by about ~58%. Exothermic, spontaneous, feasible, and monolayer adsorption was identified based on thermodynamics and isotherm analysis. Reusability testing verified the stability of the adsorbent and found that the reused adsorbent performed well for up to three thermal cycles. Comparative analysis revealed that the modified adsorbent outperformed previously reported adsorbents and unmodified Fe2MnO4 in terms of its partition coefficient and equilibrium adsorption capacity under different experimental conditions.

15.
Molecules ; 29(16)2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39202991

RESUMEN

Tribocatalysis is an emerging advanced oxidation process that utilizes the triboelectric effect, based on friction between dissimilar materials to produce charges that can initiate various catalytic reactions. In this study, pure and rare-earth-modified ZnO powders (La2O3, Eu2O3, 2 mol %) were demonstrated as efficient tribocatalysts for the removal of the tetracycline antibiotic doxycycline (DC). While the pure ZnO samples achieved 49% DC removal within 24 h at a stirring rate of 100 rpm, the addition of Eu2O3 increased the removal efficiency to 67%, and La2O3-modified ZnO powder exhibited the highest removal efficiency, reaching 80% at the same stirring rate. Additionally, increasing the stirring rate to 300 and 500 rpm led to 100% DC removal in the ZnO/La case within 18 h, with the pronounced effect of the stirring rate confirming the tribocatalytic effect. All tribocatalysts exhibited excellent recycling properties, with less than a 3% loss of activity over three cycles. Furthermore, a scavenger assay confirmed the importance of superoxide radical generation for the overall reaction rate. The results of this investigation indicate that the rare-earth-modified ZnO tribocatalysts can effectively utilize mechanical energy to decompose pollutants in contaminated water.


Asunto(s)
Antibacterianos , Metales de Tierras Raras , Óxido de Zinc , Óxido de Zinc/química , Antibacterianos/química , Metales de Tierras Raras/química , Catálisis , Tetraciclina/química , Oxidación-Reducción , Contaminantes Químicos del Agua/química
16.
Molecules ; 29(9)2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38731640

RESUMEN

We modified C3-symmetric benzene-1,3,5-tris-amide (BTA) by introducing flexible linkers in order to generate an N-centered BTA (N-BTA) molecule. The N-BTA compound formed gels in alcohols and aqueous mixtures of high-polar solvents. Rheological studies showed that the DMSO/water (1:1, v/v) gels were mechanically stronger compared to other gels, and a similar trend was observed for thermal stability. Powder X-ray analysis of the xerogel obtained from various aqueous gels revealed that the packing modes of the gelators in these systems were similar. The stimuli-responsive properties of the N-BTA towards sodium/potassium salts indicated that the gel network collapsed in the presence of more nucleophilic anions such as cyanide, fluoride, and chloride salts at the MGC, but the gel network was intact when in contact with nitrate, sulphate, acetate, bromide, and iodide salts, indicating the anion-responsive properties of N-BTA gels. Anion-induced gel formation was observed for less nucleophilic anions below the MGC of N-BTA. The ability of N-BTA gels to act as an adsorbent for hazardous anionic and cationic dyes in water was evaluated. The results indicated that the ethanolic gels of N-BTA successfully absorbed methylene blue and methyl orange dyes from water. This work demonstrates the potential of the N-BTA gelator to act as a stimuli-responsive material and a promising candidate for water purification.

17.
Molecules ; 29(2)2024 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-38257313

RESUMEN

Electronic waste (e-waste) is one of the fastest-growing waste streams in the world and Europe is classified as the first producer in terms of per capita amount. To reduce the environmental impact of e-waste, it is important to recycle it. This work shows the possibility of reusing glassy substrates, derived from the MW-assisted acidic leaching of Waste Printed Circuit Boards (WPCBs), as an adsorbent material. The results revealed an excellent adsorption capability against methylene blue (MB; aqueous solutions in the concentration range 10-5 M-2 × 10-5 M, at pH = 7.5). Comparisons were performed with reference samples such as activated carbons (ACs), the adsorbent mostly used at the industrial level; untreated PCB samples; and ground glass slides. The obtained results show that MW-treated WPCB powder outperformed both ground glass and ground untreated PCBs in MB adsorption, almost matching AC adsorption. The use of this new adsorbent obtained through the valorization of e-waste offers advantages not only in terms of cost but also in terms of environmental sustainability.

18.
Environ Monit Assess ; 196(7): 666, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38935201

RESUMEN

The metal intoxication and its associated adverse effects to humans have led to the research for development of water treatment technologies from pollution hazards. Therefore, development of cheaper water remediation technologies is more urgent than ever. Clays and clay minerals are naturally occurring, inexpensive, non-toxic materials possessing interesting chemical and physical properties. As a result of interesting surface properties, these have been developed as efficient absorbent in water remediation. Recently, clay-polymer nanocomposites have provided a cost-effective technological platform for removing contaminants from water. Covering research advancements from past 25 years, this review highlights the developments in clay-polymer nanocomposites and their advanced technical applications are evaluated with respect to the background and issues in remediation of toxic metals and organic compounds from water. The extensive analysis of literature survey of more than two decades suggests that future work need to highlight on advancement of green and cost-effective technologies. The development of understanding of the interaction and exchange between toxin and clay-polymer composites would provide new assembly methods of nanocomposites with functional molecules or nanomaterials need to be extended to increase the detection and extraction limit to parts per trillion.


Asunto(s)
Arcilla , Nanocompuestos , Polímeros , Contaminantes Químicos del Agua , Purificación del Agua , Nanocompuestos/química , Arcilla/química , Polímeros/química , Purificación del Agua/métodos , Contaminantes Químicos del Agua/análisis , Silicatos de Aluminio/química
19.
Environ Sci Technol ; 57(9): 4050-4059, 2023 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-36802506

RESUMEN

Converting biomass into biochar (BC) as a functional biocatalyst to accelerate persulfate activation for water remediation has attracted much attention. However, due to the complex structure of BC and the difficulty in identifying the intrinsic active sites, it is essential to understand the link between various properties of BC and the corresponding mechanisms promoting nonradicals. Machine learning (ML) recently demonstrated significant potential for material design and property enhancement to help tackle this problem. Herein, ML techniques were applied to guide the rational design of BC for the targeted acceleration of nonradical pathways. The results showed a high specific surface area, and O% values can significantly enhance nonradical contribution. Furthermore, the two features can be regulated by simultaneously tuning the temperatures and biomass precursors for efficient directed nonradical degradation. Finally, two nonradical-enhanced BCs with different active sites were prepared based on the ML results. This work serves as a proof of concept for applying ML in the synthesis of tailored BC for persulfate activation, thereby revealing the remarkable capability of ML for accelerating bio-based catalyst development.


Asunto(s)
Carbón Orgánico , Contaminantes Químicos del Agua , Oxidación-Reducción , Carbón Orgánico/química , Catálisis , Temperatura , Contaminantes Químicos del Agua/análisis
20.
Environ Sci Technol ; 57(12): 5024-5033, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36892275

RESUMEN

Efficient spontaneous molecular oxygen (O2) activation is an important technology in advanced oxidation processes. Its activation under ambient conditions without using solar energy or electricity is a very interesting topic. Low valence copper (LVC) exhibits theoretical ultrahigh activity toward O2. However, LVC is difficult to prepare and suffers from poor stability. Here, we first report a novel method for the fabrication of LVC material (P-Cu) via the spontaneous reaction of red phosphorus (P) and Cu2+. Red P, a material with excellent electron donating ability and can directly reduce Cu2+ in solution to LVC via forming Cu-P bonds. With the aid of the Cu-P bond, LVC maintains an electron-rich state and can rapidly activate O2 to produce ·OH. By using air, the ·OH yield reaches a high value of 423 µmol g-1 h-1, which is higher than traditional photocatalytic and Fenton-like systems. Moreover, the property of P-Cu is superior to that of classical nano-zero-valent copper. This work first reports the concept of spontaneous formation of LVC and develops a novel avenue for efficient O2 activation under ambient conditions.


Asunto(s)
Cobre , Peróxido de Hidrógeno , Peróxido de Hidrógeno/química , Fósforo , Oxidación-Reducción , Oxígeno
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