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1.
Environ Res ; 256: 119235, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38810826

RESUMEN

Dyes are the most ubiquitous organic pollutants in industrial effluents. They are highly toxic to both plants and animals; thus, their removal is paramount to the sustainability of ecosystem. However, they have shown resistance to photolysis and various biological, physical, and chemical wastewater remediation processes. Membrane removal technology has been vital for the filtration/separation of the dyes. In comparison to polymeric membranes, inorganic and mixed matrix (MM) membranes have shown potentials to the removal of dyes. The inorganic and MM membranes are particularly effective due to their high porosity, enhanced stability, improved permeability, higher enhanced selectivity and good stability and resistance to harsh chemical and thermal conditions. They have shown prospects in filtration/separation, adsorption, and catalytic degradation of the dyes. This review highlighted the advantages of the inorganic and MM membranes for the various removal techniques for the treatments of the dyes. Methods for the membranes production have been reviewed. Their application for the filtration/separation and adsorption have been critically analyzed. Their application as support for advanced oxidation processes such as persulfate, photo-Fenton and photocatalytic degradations have been highlighted. The mechanisms underscoring the efficiency of the processes have been cited. Lastly, comments were given on the prospects and challenges of both inorganic and MM membranes towards removal of the dyes from industrial effluents.


Asunto(s)
Colorantes , Residuos Industriales , Membranas Artificiales , Contaminantes Químicos del Agua , Colorantes/química , Colorantes/toxicidad , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Residuos Industriales/análisis , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Filtración/métodos , Adsorción
2.
Environ Res ; 252(Pt 3): 119024, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38692419

RESUMEN

Environmental pollution has been increasing since last decade due to increasing industrialisation and urbanisation. Various kinds ofenvironmental pollutants including carbon dioxide (CO2), dyes, pharmaceuticals, phenols, heavy metals along with many organic and inorganic species have been discovered in the various environmental compartments which possess harmful impacts tox human health, wildlife, and ecosystems. Thus, various efforts have been made through regulations, technological advancements, and public awareness campaigns to reduce the impact of the pollution. However, finding suitable alternatives to mitigate their impacts remained a challenge. Metal-organic frameworks (MOFs) are one of the advanced materials with unique features such as high porosity and stability which exhibit versatile applications in environmental remediation. Their composites with titanium oxide nanoparticles (TiO2) have been discovered to offer potential feature such as light harvesting capacity and catalytic activity. The composite integration and properties have been confirmed through characterization using surface area analysis, scanning electron/transmission electron microscopy, atomic force microscopy, fourier transformed infrared spectroscopy, X-ray diffraction analysis, X-ray photoelectron spectroscopy, thermogravimetric analysis, and others. Thus, this work rigorously discussed potential applications of the MOF@TiO2 nanomaterials for the CO2 capture and effective utilization in methanol, ethanol, acetone, acetaldehyde, and other useful products that served as fuel to various industrial processes. Additionally, the work highlights the effective performance of the materials towards photocatalytic degradation of both organic and inorganic pollutants with indepth mechanistic insights. The article will offer significant contribution for the development of sustainable and efficient technologies for the environmental monitoring and pollution mitigation.


Asunto(s)
Dióxido de Carbono , Estructuras Metalorgánicas , Titanio , Titanio/química , Dióxido de Carbono/química , Dióxido de Carbono/análisis , Estructuras Metalorgánicas/química , Aguas Residuales/química , Restauración y Remediación Ambiental/métodos , Nanopartículas/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis
3.
Environ Res ; 258: 119413, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38876422

RESUMEN

Frequent detection of terbutaline in wastewater highlights its potential risks to human health associated in the environment. Exposure to terbutaline through contaminated water sources or food chain have adverse effects to human health. This work emphasized on the removal of terbutaline from wastewater using adsorption technology. Mechanochemically synthesized [Cu(INA)2] metal-organic frameworks (MOFs) and its magnetic composite ([Cu(INA)2]-MOF@Fe3O4) are designed with higher specific surface areas and tailored features to accommodate the molecular size and structure of terbutaline. Thus, batch experiment has been conducted using the [Cu(INA)2]-MOF and [Cu(INA)2]-MOF@Fe3O4 for the terbutaline adsorption. The adsorption efficiency achieved by the MOFs was 91.8% and 99.3% for the Cu(INA)2]-MOF and [Cu(INA)2]-MOF@Fe3O4 respectively. The optimum for the adsorption study included terbutaline concentration of 40 mg/L, adsorbent dose of 5 mg/L, pH of 11, temperature of 25 °C and equilibrium time of 40 min. The kinetics and isotherms have been described by pseudo-second order and Langmuir models, while the thermodynamics revealed the exothermic and spontaneous nature of the process. The promising performance of the MOFs is manifested on the ease of regeneration and reusability, achieving adsorption efficiency of 85.0% and 94.7% by the Cu(INA)2]-MOF and [Cu(INA)2]-MOF@Fe3O4, respectively at five consecutive cycles. The higher performance of the MOFs demonstrates their excellent potentialities for the terbutaline adsorption from the aqueous solution.


Asunto(s)
Cobre , Terbutalina , Aguas Residuales , Contaminantes Químicos del Agua , Adsorción , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Aguas Residuales/química , Terbutalina/química , Cobre/química , Estructuras Metalorgánicas/química , Nanopartículas Magnéticas de Óxido de Hierro/química , Cinética , Compuestos Férricos/química
4.
J Environ Manage ; 360: 121138, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38749131

RESUMEN

In the pursuit of alternatives for conventional diesel, sourced from non-renewable fossil fuel, biodiesel has gained attentions for its intrinsic benefits. However, the commercial production process for biodiesel is still not sufficiently competitive. This review analyses microalgal lipid, one of the important sources of biodiesel, and its cultivation techniques with recent developments in the technical aspects. In fact, the microalgal lipids are the third generation feedstock, used for biodiesel production after its benefits outweigh that of edible vegetable oils (first generation) and non-edible oils (second generation). The critical factors influencing microalgal growth and its lipid production and accumulation are also discussed. Following that is the internal enhancement for cellular lipid production through genetic engineering. Moreover, the microalgae cultivation data modelling was also rationalized, with a specific focus on growth kinetic models that allow for the prediction and optimization of lipid production. Finally, the machine learning and environmental impact analysis are as well presented as important aspects to consider in fulfilling the prime objective of commercial sustainability to produce microalgal biodiesel.


Asunto(s)
Biocombustibles , Lípidos , Microalgas , Microalgas/metabolismo , Microalgas/crecimiento & desarrollo , Lípidos/química
5.
Environ Geochem Health ; 46(4): 145, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38568460

RESUMEN

Frequent detection of sulfonamides (SAs) pharmaceuticals in wastewater has necessitated the discovery of suitable technology for their sustainable remediation. Adsorption has been widely investigated due to its effectiveness, simplicity, and availability of various adsorbent materials from natural and artificial sources. This review highlighted the potentials of carbon-based adsorbents derived from agricultural wastes such as lignocellulose, biochar, activated carbon, carbon nanotubes graphene materials as well as organic polymers such as chitosan, molecularly imprinted polymers, metal, and covalent frameworks for SAs removal from wastewater. The promising features of these materials including higher porosity, rich carbon-content, robustness, good stability as well as ease of modification have been emphasized. Thus, the materials have demonstrated excellent performance towards the SAs removal, attributed to their porous nature that provided sufficient active sites for the adsorption of SAs molecules. The modification of physico-chemical features of the materials have been discussed as efficient means for enhancing their adsorption and reusable performance. The article also proposed various interactive mechanisms for the SAs adsorption. Lastly, the prospects and challenges have been highlighted to expand the knowledge gap on the application of the materials for the sustainable removal of the SAs.


Asunto(s)
Nanotubos de Carbono , Aguas Residuales , Polímeros , Sulfonamidas , Sulfanilamida , Preparaciones Farmacéuticas
6.
Environ Res ; 221: 115326, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36690243

RESUMEN

Perfluorooctanoic acid (PFOA) has been identified as the most toxic specie of the family of perfluorinated carboxylic acids (PFCAs). It has been widely distributed and frequently detected in environmental wastewater. The compound's unique features such as inherent stability, rigidity, and resistance to harsh chemical and thermal conditions, due to its multiple and strong C-F bonds have resulted in its resistance to conventional wastewater remediations. Photolysis and bioremediation methods have been proven to be inefficient in their elimination, hence this article presents intensive literature studies and summarized findings reported on the application of advanced oxidation processes (AOPs) and photocatalytic degradation techniques as the best alternatives for the PFOA elimination from wastewater. Techniques of persulfate, photo-Fenton, electrochemical, photoelectrochemical and photocatalytic degradation have been explored and their mechanisms for the degradation and defluorination of the PFOA have been demonstrated. The major advantage of AOPs techniques has been centralized on the generation of active radicals such as sulfate (SO4•-) hydroxyl (•OH). While for the photocatalytic process, photogenerated species (electron (e) and holes (h + vb)) initiated the process. These active radicals and photogenerated species possessed potentiality to attack the PFOA molecule and caused the cleavage of the C-C and C-F bonds, resulting in its efficient degradation. Shorter-chain PFCAs have been identified as the major intermediates detected and the final stage entails its complete mineralization to carbon dioxide (CO2) and fluoride ion (F-). The prospects and challenges associated with the outlined techniques have been highlighted for better understanding of the subject matter for the PFOA elimination from real wastewaters.


Asunto(s)
Fluorocarburos , Contaminantes Químicos del Agua , Aguas Residuales , Caprilatos , Oxidación-Reducción , Ácidos Carboxílicos , Contaminantes Químicos del Agua/química
7.
Environ Res ; 231(Pt 2): 116102, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37196688

RESUMEN

Perfluoroalkyl carboxylic acids (PFCAs) are sub-class of perfluoroalkyl substances commonly detected in water matrices. They are persistent in the environment, hence highly toxic to living organisms. Their occurrence at trace amount, complex nature and prone to matrix interference make their extraction and detection a challenge. This study consolidates current advancements in solid-phase extraction (SPE) techniques for the trace-level analysis of PFCAs from water matrices. The advantages of the methods in terms of ease of applications, low-cost, robustness, low solvents consumption, high pre-concentration factors, better extraction efficiency, good selectivity and recovery of the analytes have been emphasized. The article also demonstrated effectiveness of some porous materials for the adsorptive removal of the PFCAs from the water matrices. Mechanisms of the SPE/adsorption techniques have been discussed. The success and limitations of the processes have been elucidated.


Asunto(s)
Fluorocarburos , Contaminantes Químicos del Agua , Humanos , Agua , Fluorocarburos/análisis , Ácidos Carboxílicos/análisis , Adsorción , Extracción en Fase Sólida/métodos , Contaminantes Químicos del Agua/análisis
8.
Environ Res ; 233: 116533, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37394167

RESUMEN

Changing the growth environment for microalgae can overall lead to the fundamental alteration in cellular biochemicals whilst attaching onto palm kernel expeller (PKE) waste to form adhesion complex in easing harvesting at stationary growth phase. This study had initially optimized the PKE dosage, light intensity and photoperiod in maximizing the attached microalgal productivity being attained at 0.72 g/g day. Lipid content increased progressively from pH 3 to pH 11, with the highest value observed at pH 11. Meanwhile, in terms of protein and carbohydrate contents, the highest values were obtained by cultivation medium of pH 5 with 9.92 g and 17.72 g, respectively followed by pH 7 with 9.16 g and 16.36 g, respectively. Moreover, the findings also suggested that the low pH mediums utilized polar interactions in the formation of complexes between PKE and microalgae, whereas at higher pH levels, the non-polar interactions became more significant. The work of attachment was thermodynamically favourable towards the attachment formation with values greater than zero which was also aligned with the microscopic surface topography, i.e., revealing a clustering pattern of microalgae colonizing the PKE surface. These findings contribute to comprehensive understanding of optimizing growth condition and harvesting strategy of attached microalgae in attaining the cellular biochemical components, facilitating the development of efficient and sustainable bioresource utilization.


Asunto(s)
Microalgas , Biomasa
9.
Molecules ; 27(15)2022 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-35897923

RESUMEN

Successful synthesis of ZnO-chitosan nanocomposites was conducted for the removal of methylene blue from an aqueous medium. Remarkable performance of the nanocomposites was demonstrated for the effective uptake of the dye, thereby achieving 83.77, 93.78 and 97.93 mg g-1 for the chitosan, 5 wt.% ZnO-Chitosan and 10 wt.% ZnO-Chitosan, respectively. The corresponding adsorption efficiency was 88.77, 93.78 and 97.95 for the chitosan, 5 wt.% ZnO-Chitosan and 10 wt.% ZnO-Chitosan, respectively. Upon regeneration, good reusability of the nanocomposites was manifested for the continuous removal of the dye up to six consecutive cycles. The adsorption process was kinetically described by a pseudo-first order model, while the isotherms were best fitted by the Langmuir model.


Asunto(s)
Quitosano , Nanocompuestos , Contaminantes Químicos del Agua , Óxido de Zinc , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Azul de Metileno , Aguas Residuales
10.
Int J Biol Macromol ; 269(Pt 1): 131759, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38679272

RESUMEN

Among biopolymer-based adsorbents, composites in the form of beads have shown promising results in terms of high adsorption capacity and ease of separation from the effluents. This review addresses the potential of biopolymer-based beads to remediate wastewaters polluted with emerging organic contaminants, for instance dyes, active pharmaceutical ingredients, pesticides, phenols, oils, polyaromatic hydrocarbons, and polychlorinated biphenyls. High adsorption capacities up to 2541.76 mg g-1 for dyes, 392 mg g-1 for pesticides and phenols, 1890.3 mg g-1 for pharmaceuticals, and 537 g g-1 for oils and organic solvents have been reported. The review also attempted to convey to its readers the significance of wastewater treatment through adsorption by providing an overview on decontamination technologies of organic water contaminants. Various preparation methods of biopolymer-based gel beads and adsorption mechanisms involved in the process of decontamination have been summarized and analyzed. Therefore, we believe there is an urge to discuss the current state of the application of biopolymer-based gel beads for the adsorption of organic pollutants from wastewater and future perspectives in this regard since it is imperative to treat wastewater before releasing into freshwater bodies.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Purificación del Agua , Aguas Residuales/química , Contaminantes Químicos del Agua/aislamiento & purificación , Contaminantes Químicos del Agua/química , Adsorción , Biopolímeros/química , Purificación del Agua/métodos , Compuestos Orgánicos/química , Compuestos Orgánicos/aislamiento & purificación , Microesferas
11.
Sci Rep ; 14(1): 5589, 2024 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-38453990

RESUMEN

The utilization of plants for the production of metallic nanoparticles is gaining significant attention in research. In this study, we conducted phytochemical screening of Alstonia scholaris (A. scholaris) leaves extracts using various solvents, including chloroform, ethyl acetate, n-hexane, methanol, and water. Our findings revealed higher proportions of flavonoids and alkaloids in both solvents compared to other phytochemical species. In the methanol, extract proteins, anthraquinone and reducing sugar were not detected. On the other hand, the aqueous extract demonstrated the presence of amino acids, reducing sugar, phenolic compounds, anthraquinone, and saponins. Notably, ethyl acetate and chloroform extracts displayed the highest levels of bioactive compounds among all solvents. Intrigued by these results, we proceeded to investigate the antibacterial properties of the leaf extracts against two major bacterial strains, Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). All extracts exhibited significant zones of inhibition against both bacterial isolates, with S. aureus showing higher susceptibility compared to E. coli. Notably, the methanol extract displayed the most potent I hibitory effect against all organisms. Inspired by the bioactivity of the methanol extract, we employed it as a plant-based material for the green synthesis of copper nanoparticles (Cu-NPs). The synthesized Cu-NPs were characterized using Fourier infrared spectroscopy (FT-IR), UV-visible spectroscopic analysis, and scanning electron microscopy (SEM). The observed color changes confirmed the successful formation of Cu-NPs, while the FTIR analysis matched previously reported peaks, further verifying the synthesis. The SEM micrographs indicated the irregular shapes of the surface particles. From the result obtained by energy dispersive X-ray spectroscopic analysis, Cu has the highest relative abundance of 67.41 wt%. Confirming the purity of the Cu-NPs colloid. These findings contribute to the growing field of eco-friendly nanotechnology and emphasize the significance of plant-mediated approaches in nanomaterial synthesis and biomedical applications.


Asunto(s)
Acetatos , Alstonia , Antiinfecciosos , Nanopartículas del Metal , Cobre/química , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus , Escherichia coli , Metanol/farmacología , Cloroformo/farmacología , Extractos Vegetales/farmacología , Extractos Vegetales/química , Antiinfecciosos/farmacología , Antibacterianos/química , Nanopartículas del Metal/química , Fitoquímicos/farmacología , Solventes/farmacología , Azúcares/farmacología , Antraquinonas/farmacología , Pruebas de Sensibilidad Microbiana
12.
Chemosphere ; 351: 141218, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38266876

RESUMEN

The widespread consumption of pharmaceutical drugs and their incomplete breakdown in organisms has led to their extensive presence in aquatic environments. The indiscriminate use of antibiotics, such as sulfonamides, has contributed to the development of drug-resistant bacteria and the persistent pollution of water bodies, posing a threat to human health and the safety of the environment. Thus, it is paramount to explore remediation technologies aimed at decomposing and complete elimination of the toxic contaminants from pharmaceutical wastewater. The review aims to explore the utilization of metal-oxide nanoparticles (MONPs) and graphitic carbon nitrides (g-C3N4) in photocatalytic degradation of sulfonamides from wastewater. Recent advances in oxidation techniques such as photocatalytic degradation are being exploited in the elimination of the sulfonamides from wastewater. MONP and g-C3N4 are commonly evolved nano substances with intrinsic properties. They possessed nano-scale structure, considerable porosity semi-conducting properties, responsible for decomposing wide range of water pollutants. They are widely applied for photocatalytic degradation of organic and inorganic substances which continue to evolve due to the low-cost, efficiency, less toxicity, and more environmentally friendliness of the materials. The review focuses on the current advances in the application of these materials, their efficiencies, degradation mechanisms, and recyclability in the context of sulfonamides photocatalytic degradation.


Asunto(s)
Grafito , Nanopartículas del Metal , Compuestos de Nitrógeno , Óxidos , Humanos , Sulfonamidas , Aguas Residuales , Sulfanilamida , Preparaciones Farmacéuticas , Catálisis
13.
Chemosphere ; 362: 142630, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38897321

RESUMEN

Microplastics (MPs) and their co-pollutants pose significant threats to soil and marine environments, necessitating understanding of their colonization processes to combat the plastic pandemic and protect ecosystems. MPs can act as invisible carriers, concentrating and transporting pollutants, leading to a more widespread and potentially toxic impact than the presence of either MPs or the pollutants alone. Analyzing the sorption and desorption dynamics of MPs is crucial for understanding pollutants amplification and predicting the fate and transport of pollutants in soil and marine environments. This review provides an in-depth analysis of the sorption and desorption dynamics of MPs, highlighting the importance of considering these dynamics in ecotoxicological risk assessment of MPs pollution. The review identifies limitations of current frameworks that neglect these interactions and proposes incorporating sorption and desorption data into robust frameworks to improve the ability to predict ecological risks posed by MPs and co-pollutants in soil and marine environments. However, failure to address the interplay between sorption and desorption can result in underestimation of the true impact of MPs and co-pollutants, affecting livelihoods and agro-employments, and exacerbate poverty and community disputes (SDGs 1, 2, 3, 8, 9, and 16). It can also affect food production and security (SDG 2), life below water and life on land (DSGs 14 and 15), cultural practices, and natural heritage (SDG 11.4). Hence, it is necessary to develop new approaches to ecotoxicological risk assessment that consider sorption and desorption processes in the interactions between the components in the framework to address the identified limitations.


Asunto(s)
Ecotoxicología , Monitoreo del Ambiente , Microplásticos , Contaminantes del Suelo , Suelo , Contaminantes Químicos del Agua , Microplásticos/análisis , Microplásticos/toxicidad , Microplásticos/química , Medición de Riesgo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/química , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/toxicidad , Suelo/química , Ecosistema , Adsorción
14.
Chemosphere ; 343: 140223, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37734509

RESUMEN

Covalent organic frameworks (COFs) are class of porous coordination polymers made up of organic building blocks joined together by covalent bonding through thermodynamic and controlled reversible polymerization reactions. This review discussed versatile applications of COFs for remediation of wastewater containing dyes, emphasizing the advantages of both pristine and modified materials in adsorption, membrane separation, and advanced oxidations processes. The excellent performance of COFs towards adsorption and membrane filtration has been centered to their higher crystallinity and porosity, exhibiting exceptionally high surface area, pore size and pore volumes. Thus, they provide more active sites for trapping the dye molecules. On one hand, the photocatalytic performance of the COFs was attributed to their semiconducting properties, and when coupled with other functional semiconducting materials, they achieve good mechanical and thermal stabilities, positive light response, and narrow band gap, a typical characteristic of excellent photocatalysts. As such, COFs and their composites have demonstrated excellent potentialities for the elimination of the dyes.

15.
Polymers (Basel) ; 15(2)2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36679278

RESUMEN

Corrosion prevention has been a global phenomenon, particularly in metallic and construction engineering. Most inhibitors are expensive and toxic. Therefore, developing nontoxic and cheap corrosion inhibitors has been a way forward. In this work, L-arginine was successfully grafted on chitosan by the thermal technique using a reflux condenser. This copolymer was characterized by Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and X-ray diffraction (XRD). The corrosion inhibition performance of the composite polymer was tested on mild steel in 0.5M HCl by electrochemical methods. The potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) results were consistent. The inhibition efficiency at optimum concentration rose to 91.4%. The quantum chemical calculation parameters show good properties of the material as a corrosion inhibitor. The molecular structure of the inhibitor was subjected to density functional theory (DFT) to understand its theoretical properties, and the results confirmed the inhibition efficiency of the grafted polymer for corrosion prevention.

16.
R Soc Open Sci ; 8(1): 201553, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33614087

RESUMEN

Effective removal of 4-chloro-2-methylphenoxyacetic acid (MCPA), an emerging agrochemical contaminant in water with carcinogenic and mutagenic health effects has been reported using hydrothermally synthesized MIL-101(Cr) metal-organic framework (MOF). The properties of the MOF were ascertained using powdered X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermal gravimetric analysis (TGA), field emission scanning electron microscopy (FESEM) and surface area and porosimetry (SAP). The BET surface area and pore volume of the MOF were 1439 m2 g-1 and 0.77 cm3 g-1, respectively. Artificial neural network (ANN) model was significantly employed for the accurate prediction of the experimental adsorption capacity (qe ) values with minimal error. A rapid removal of the pollutant (99%) was recorded within short time (approx. 25 min), and the reusability of the MOF (20 mg) was achieved up to six cycles with over 90% removal efficiency. The kinetics, isotherm and thermodynamics of the process were described by the pseudo-second-order, Freundlich and endothermic adsorption, respectively. The adsorption process is spontaneous based on the negative Gibbs free energy values. The significant correlation between the experimental findings and simulation results suggests the great potential of MIL-101(Cr) for the remediation of MCPA from water matrices.

17.
RSC Adv ; 10(70): 43213-43224, 2020 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-35514937

RESUMEN

An aluminium-based metal-organic framework ((MOF), MIL-53(Al)), was hydrothermally synthesized, characterized and applied for the remediation of the herbicides dicamba (3,6-dichloro-2-methoxy benzoic acid) and 4-chloro-2-methylphenoxyacetic acid (MCPA) in aqueous medium. Response surface methodology (RSM) and artificial neural network (ANN) were used to design, optimize and predict the non-linear relationships between the independent and dependent variables. The shared interaction of the effects of key response parameters on the adsorption capacity were assessed using the central composite design-RSM and ANN optimization models. The optimum adsorption capacities for dicamba and MCPA are 228.5 and 231.9 mg g-1, respectively. The RSM ANOVA results showed significant p-values, with coefficients of determination (R 2) = 0.988 and 0.987 and R 2 adjusted = 0.974 and 0.976 for dicamba and MCPA, respectively. The ANN prediction model gave R 2 = 0.999 and 0.999, R 2 adjusted = 0.997 and 0.995 and root mean square errors (RMSEs) of 0.001 and 0.004 for dicamba and MCPA, respectively. In each set of experimental conditions used for the study, the ANN gave better prediction than the RSM, with high accuracy and minimal error. The rapid removal (∼25 min), reusability (5 times) and good agreement between the experimental findings and simulation results suggest the great potential of MIL-53(Al) for the remediation of dicamba and MCPA from water matrices.

18.
Polymers (Basel) ; 12(11)2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-33182825

RESUMEN

Water-borne emerging pollutants are among the greatest concern of our modern society. Many of these pollutants are categorized as endocrine disruptors due to their environmental toxicities. They are harmful to humans, aquatic animals, and plants, to the larger extent, destroying the ecosystem. Thus, effective environmental remediations of these pollutants became necessary. Among the various remediation techniques, adsorption and photocatalytic degradation have been single out as the most promising. This review is devoted to the compilations and analysis of the role of metal-organic frameworks (MOFs) and their composites as potential materials for such applications. Emerging organic pollutants, like dyes, herbicides, pesticides, pharmaceutical products, phenols, polycyclic aromatic hydrocarbons, and perfluorinated alkyl substances, have been extensively studied. Important parameters that affect these processes, such as surface area, bandgap, percentage removal, equilibrium time, adsorption capacity, and recyclability, are documented. Finally, we paint the current scenario and challenges that need to be addressed for MOFs and their composites to be exploited for commercial applications.

19.
RSC Adv ; 9(71): 41490-41501, 2019 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-35541585

RESUMEN

Three adsorbents based on the metal-organic frameworks (MOFs), viz.; MIL-88(Fe), NH2-MIL-88(Fe), and mixed-MIL-88(Fe) were synthesized using a microwave-assisted solvothermal technique. The as-synthesized MOFs were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), field emission scanning microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FTIR). The MOFs were shown to possess highly crystalline and porous structures with specific surface areas of 1240, 941, and 1025 m2 g-1 and pore volumes of 0.7, 0.6 and 0.6 m3 g-1 for MIL-88(Fe), NH2-MIL-88(Fe) and mixed-MIL-88(Fe), respectively. Faster removal of a model polycyclic aromatic hydrocarbon, anthracene (ANT) within 25 minutes, was achieved when these MOFs were used as adsorbents in water. The removal efficiency was 98.3, 92.4 and 95.8% for MIL-88(Fe), NH2-MIL-88(Fe) and mixed-MIL-88(Fe), respectively. The kinetics and isotherms of the process were best statistically described by pseudo-second-order and Langmuir models, respectively, while the thermodynamic studies revealed the exothermic and spontaneous nature of the process. Docking simulations were found to be consistent with the experimental results with MIL-88(Fe) showing the best binding capacity with the ANT molecule.

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