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1.
Chemosphere ; : 142729, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38971438

RESUMO

17 global Sustainable Development Goals (SDGs) were established through the adoption of the 2030 Agenda for Sustainable Development by all United Nations members. Clean water and sanitation (SDG 6) and industry, innovation, and infrastructure (SDG 9) are the SDGs focus of this work. Of late, various new companies delivering metal-organic frameworks (MOFs) have blossomed and moved the field of adsorption utilizing MOFs to another stage. Inside this unique circumstance, this article aims to catch recent advancements in the field of MOFs and the utilizations of MOFs relate to the expulsion of arising contaminations that present huge difficulties to water quality because of their steadiness and possible damage to environments and human wellbeing. Customary water treatment techniques regularly neglect to eliminate these poisons, requiring the advancement of novel methodologies. This study overviews engineering techniques for controlling MOF characteristics for better flexibility, stability, and surface area. A current report on MOFs gathered new perspectives that are amicably discussed in emergent technologies and extreme applications towards environmental sectors. Various applications in many fields that exploit MOFs are being fostered, including gas storage, fluid separation, adsorbents, catalysis, medication delivery, and sensor utilizations. The surface area of a wide range of MOFs ranges from 103 to 104 m2/g, which exceeds the standard permeability of several material designs. MOFs with extremely durable porosity are more significant in their assortment and variety than other classes of porous materials. The work outlines the difficulties encountered in the synthesis steps and suggests ways to make use of MOFs' value in a variety of contexts. This caters to creating multivariate systems enclosed with numerous functionalities, leading to the synthesis of MOFs that offer a synergistic blend of in-built properties and exclusive applications. Additionally, the MOF-related future development opportunities and challenges are discussed.

2.
Chemosphere ; 361: 142533, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38849099

RESUMO

Development of effective adsorbents for the removal of contaminants from wastewater is indispensable due to increasing water scarcity and a lack of pure drinking water, which are prevailing as a result of rapid industrialization and population growth. Recently, the development of new adsorbents and their effective use without generating secondary waste is receiving huge consideration. In order to protect the environment from primary and secondary pollution, the development of adsorbents from wastes and their recycling have become conventional practices aimed at waste management. As a result, significant progress has been made in the synthesis of new porous carbon and metal-organic frameworks as adsorbents, with the objective of using them for the removal of pollutants. While many different kinds of pollutants are produced in the environment, drug pollutants are the most vicious because of their tendency to undergo significant structural changes, producing metabolites and residues with entirely different properties compared to their parent compounds. Chemical reactions involving oxidation, hydrolysis, and photolysis transform drugs. The resulting compounds can have detrimental effects on living beings that are present in soil and water. This review stresses the development of adsorbents with adjustable porosities for the broad removal of primary drug pollutants and their metabolites, which are formed as a result of drug transformations in environmental matrices. This keeps adsorbents from building up in the environment and prevents them from becoming significant pollutants in the future. Additionally, it stops secondary pollution caused by the deterioration of the used adsorbents. Focus on the development of effective adsorbents with flexible porosities allows for the complete removal of coexisting contaminants and makes a substantial contribution to wastewater management. In order to concentrate more on the development of flexible pore adsorbents, it is crucial to comprehend the milestones reached in the research and applications of porous magnetic adsorbents based on metal and carbon, which are discussed here.


Assuntos
Carbono , Estruturas Metalorgânicas , Águas Residuárias , Poluentes Químicos da Água , Porosidade , Adsorção , Poluentes Químicos da Água/química , Estruturas Metalorgânicas/química , Carbono/química , Águas Residuárias/química , Purificação da Água/métodos , Metais/química , Preparações Farmacêuticas/química
3.
Sci Rep ; 14(1): 12818, 2024 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834602

RESUMO

Recent years have seen an increase in research on biodiesel, an environmentally benign and renewable fuel alternative for traditional fossil fuels. Biodiesel might become more cost-effective and competitive with diesel if a solid heterogeneous catalyst is used in its production. One way to make biodiesel more affordable and competitive with diesel is to employ a solid heterogeneous catalyst in its manufacturing. Based on X-ray diffraction (XRD) and Fourier Transform infrared spectroscopy (FTIR), the researchers in this study proved their hypothesis that iron oxide core-shell nanoparticles were generated during the green synthesis of iron-based nanoparticles (FeNPs) from Camellia Sinensis leaves. The fabrication of spherical iron nanoparticles was successfully confirmed using scanning electron microscopy (SEM). As a heterogeneous catalyst, the synthesised catalyst has shown potential in facilitating the conversion of algae oil into biodiesel. With the optimal parameters (0.5 weight percent catalytic load, 1:6 oil-methanol ratio, 60 °C reaction temperature, and 1 h and 30 min reaction duration), a 93.33% yield was attained. This may be due to its acid-base property, chemical stability, stronger metal support interaction. Furthermore, the catalyst was employed for transesterification reactions five times after regeneration with n-hexane washing followed by calcination at 650 °C for 3 h.


Assuntos
Biocombustíveis , Camellia sinensis , Folhas de Planta , Folhas de Planta/química , Catálise , Camellia sinensis/química , Ferro/química , Nanopartículas Metálicas/química , Difração de Raios X , Esterificação , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Environ Geochem Health ; 46(7): 248, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874631

RESUMO

All pests can be eliminated with the help of pesticides, which can be either natural or synthetic. Because of the excessive use of pesticides, it is harmful to both ecology and people's health. Pesticides are categorised according to several criteria: their chemical composition, method of action, effects, timing of use, source of manufacture, and formulations. Many aquatic animals, birds, and critters live in danger owing to hazardous pesticides. Metaldehyde is available in various forms and causes significant impact even when small amounts are ingested. Metaldehyde can harm wildlife, including dogs, cats, and birds. This review discusses pesticides, their types and potential environmental issues, and metaldehyde's long-term effects. In addition, it examines ways to eliminate metaldehyde from the aquatic ecosystem before concluding by anticipating how pesticides may affect society. The metal-organic framework and other biosorbents have been appropriately synthesized and subsequently represent the amazing removal of pesticides from effluent as an enhanced adsorbent, such as magnetic nano adsorbents. A revision of the risk assessment for metaldehyde residuals in aqueous sources is also attempted.


Assuntos
Acetaldeído , Praguicidas , Poluentes Químicos da Água , Acetaldeído/análogos & derivados , Animais , Medição de Risco , Humanos , Adsorção , Estruturas Metalorgânicas/química
5.
Environ Res ; 222: 115332, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36709874

RESUMO

The oil contamination in aquatic system is considered as most serious environmental issues and identifying a suitable ecofriendly solution for this oil pollution management is critical. Hence, this research was designed to evaluate the oils (petrol, diesel, engine oil, and crude oil) adsorptive features through raw lemon grass adsorbent, physically/chemically treated adsorbents. Initially, such raw and treated adsorbents were characterized by Scanning Electron Microscope (SEM), Fourier transform infrared spectroscopy (FTIR), and Energy-Dispersive X-ray Spectroscopy (EDS) analysis. These characterization techniques revealed that the lemon grass adsorbent had considerable level of pollutant adsorption potentials owing to porous morphological structure, active functional groups and pollutants interaction with chemical elements. The physically treated adsorbent exhibited better adsorption characteristics than others. Accordingly, the petrol adsorption potential of raw adsorbent, physically treated and chemically treated ones was discovered as their weight incremented up to 2.0, 3.0, and 1.5 times their initial weight, respectively. Similarly, the weight of raw form, physically and chemically treated ones on diesel had increased significantly, up to 2.5 times, 4.0 times, and 2.0 times, respectively. It was evaluated that the weight of these tested adsorbents on engine oil incremented by 3.5, 5.0, and 3.0 times their initial weight, while on crude oil these incremented by 4.0, 6.0, and 4.0 times their initial weight respectively. When the media are compared, it's indeed evident about absorption which is preferred as follows: Crude oil, engine oil, diesel, and petrol. The physically treated lemon grass adsorbent showed maximum adsorption and retention potential than others. The kinetic study reveals that the pseudo second order kinetics is the best fit for the adsorption of oil with R2 value of 0.99.


Assuntos
Cymbopogon , Petróleo , Poluentes Químicos da Água , Adsorção , Gasolina , Óleos , Cinética , Poluentes Químicos da Água/química , Espectroscopia de Infravermelho com Transformada de Fourier , Concentração de Íons de Hidrogênio
6.
Environ Res ; 222: 115336, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36706901

RESUMO

The exploitation of petroleum derivatives to meet the energy demands of the cutting edge is thought of as impractical because of asset shortage. The current necessitates that the world community improves future energy sources by developing sustainable, ecofriendly alternatives. In this work, biodiesel is produced through the transesterification of Catharanthus roseus seed oil with a barium-doped CaO heterogeneous nanocatalyst. The catalyst characterization is assessed using FTIR, GC-FID, EDAX, XRD, and SEM. The optimum conditions of time (70 min), temperature (58 °C), the molar ratio of methanol: oil is 15:1, and catalyst load (4% w/w) resulted in a conversion of the maximum biodiesel yield of 91.83%. Finally, by using Catharanthus roseus as a feedstock, the low optimal reaction conditions contribute to the development of the economic impact of biodiesel synthesis. Biodiesel blend (B20) containing barium-doped CaO nanoparticles showed better combustion engine performance and lower emissions than fossil fuels.


Assuntos
Biocombustíveis , Catharanthus , Bário , Cinética , Sementes , Catálise
7.
Sci Total Environ ; 825: 153897, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35182637

RESUMO

Water is one of the important gifts to mankind. In recent days the accessibility of pharmaceuticals in the environment is progressively a worldwide concern. The significant wellspring of these contaminations in water assets is drugs for human use or veterinary medications. Intermediates, active metabolites and raw materials present in water from pharmaceutical industry waste because of incomplete sewage treatment systems. Various pharmaceutical components such as analgesic/antipyretics such as Ibuprofen (57.9-104 ng/L), Diclofenac (17-129 ng/L), antibiotics such as Sulfamethoxazole (28.7-124.5 ng/L), Sulfamethazine (29.2-83.9 ng/L), Azithromycin (10-68 ng/L), psychiatric drug such as Carbamazepine (9.3-92.4 ng/L), stimulants such as caffeine greater than 55 ng/L, antidepressants, antihypertensive, contraceptives etc., are present in water resources and have been detected in mg/L to µg/L range. The synergic effects and ecotoxicological hazard assessment must be developed. Studies demonstrate that these drugs might cause morphological, metabolic and sex alterations on sea-going species, and interruption of biodegradation activities. Hazard analysis and assessments are in progress. However, the conventional effluent treatment methods are not sufficient to remove API (active pharmaceutical ingredients) from this water effectively. There is necessitate for continuous monitoring of the pharmaceutical compounds in aquatic ecosystem to save the environment and living form of lives from health hazards. This work highlights the hazards, environmental assessment and the mitigation measures of pharmaceutical pollutants.


Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental/métodos , Humanos , Preparações Farmacêuticas , Medição de Risco , Águas Residuárias/química , Água , Poluentes Químicos da Água/análise , Recursos Hídricos
8.
IET Nanobiotechnol ; 14(4): 289-299, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32463019

RESUMO

The extensive discomfort in the expulsion of toxic pollutants even at mild concentrations has demanded the need for prompt methods for the evacuation of dyes and heavy metals. The effective method for depuration of dye from the effluent is by sorption. Chitosan is a bio-polymer which is gaining an increasing interest as one of the sorbents. It was obtained from the crab shells by undergoing several chemical processes and used as an adsorbent for dye, metal removal and also for pharmaceutical purposes. Cross linking it with other co polymers will increase the capacity of adsorption to a maximum level. Fish scales are considered to be a major waste in the food industry and since it takes a long time for decomposing it is considered to be one of the pollutants. Hence it is utilised by converting it into activated carbon by preliminary treatment and into a muffle furnace. The obtained activated carbon is combined with chitosan by using a cross linker and utilised for adsorption mechanism. To analyse the effect of chitosan cross linked with activated carbon obtained from fish scales in adsorption of dye Reactive Blue 9 (RB9) to evaluate the adsorption studies, kinetics, mass transfer studies, thermodynamics of the bio adsorbent.


Assuntos
Escamas de Animais/química , Quitosana/química , Corantes , Nanopartículas/química , Poluentes Químicos da Água , Adsorção , Animais , Braquiúros , Carbono/química , Corantes/química , Corantes/isolamento & purificação , Peixes , Cinética , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
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