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1.
J Environ Manage ; 363: 121254, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38850909

RESUMO

Despite being composed of recyclable materials, the main technological challenge of multilayer carton packs involves the efficient decompatibilization of the cellulosic, polymeric, and metallic phases. Here, a simple two-step mechanochemical process is described that uses only aqueous media and mechanical force to promote phase separation in order to fully recycle multi-layer carton packaging. The first step produces value-added micro- and nanocellulose, while in the second step, aluminum is extracted, forming precipitated aluminum and aluminum oxyhydroxides. Solid polyethylene (PE) remains with a degree of purity defined by the process efficiency. The results show that cellulose is efficiently extracted and converted into micro- and nanocellulose after 15 min of milling. In the second stage, approximately 90% of the aluminum is extracted from the PE after 15 min of milling. Due to the separation and drying medium conditions, the finely divided particles of extracted aluminum also have oxyhydroxides in their composition. It is believed that a passivation layer forms on the metallic aluminum particle. The techno-economic analysis revealed a positive net present value (NPV) of $17.5 million, with a minimum selling price of 1.62 USD/kg of cellulose. The environmental analysis concluded that most of the environmental impact of the process is associated with the entry of carton packages into the system, incorporating a small environmental load related to the industrial process. The results indicate a promising option toward a circular economy and carbon neutrality.


Assuntos
Celulose , Reciclagem , Celulose/química , Alumínio/química , Polietileno/química
2.
Int J Pharm ; 659: 124219, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38734277

RESUMO

This work aimed at formulating a trilaminate dressing loaded with tranexamic acid. It consisted of a layer of 3 % sodium hyaluronate to initiate hemostasis. It was followed by a mixed porous layer of 5 % polyvinyl alcohol and 2 % kappa-carrageenan. This layer acted as a drug reservoir that controlled its release. The third layer was 5 % ethyl cellulose backing layer for unidirectional release of tranexamic acid towards the wound. The 3 layers were physically crosslinked by hydrogen bonding as confirmed by Infrared spectroscopy. Swelling and release studies were performed, and results proposed that increasing number of layers decreased swelling properties and sustained release of tranexamic acid for 8 h. In vitro blood coagulation study was performed using human blood and showed that the dressing significantly decreased coagulation time by 70.5 % compared to the negative control. In vivo hemostatic activity was evaluated using tail amputation model in Wistar rats. Statistical analysis showed the dressing could stop bleeding in a punctured artery of the rat tail faster than the negative control by 59 %. Cranial bone defect model in New Zealand rabbits was performed to check for bone hemostasis and showed significant decrease in the hemostatic time by 80 % compared to the control.


Assuntos
Bandagens , Carragenina , Hemorragia , Ácido Hialurônico , Álcool de Polivinil , Ratos Wistar , Ácido Tranexâmico , Animais , Coelhos , Hemorragia/tratamento farmacológico , Hemorragia/prevenção & controle , Álcool de Polivinil/química , Ácido Tranexâmico/química , Ácido Tranexâmico/administração & dosagem , Ácido Hialurônico/química , Humanos , Celulose/análogos & derivados , Celulose/química , Masculino , Modelos Animais de Doenças , Ratos , Liberação Controlada de Fármacos , Coagulação Sanguínea/efeitos dos fármacos , Antifibrinolíticos/química , Antifibrinolíticos/administração & dosagem , Antifibrinolíticos/farmacologia , Hemostáticos/química , Hemostáticos/farmacologia , Hemostáticos/administração & dosagem , Preparações de Ação Retardada
3.
ACS Appl Mater Interfaces ; 16(23): 30385-30395, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38816917

RESUMO

In the present work, we explored Lewis acid catalysis, via FeCl3, for the heterogeneous surface functionalization of cellulose nanofibrils (CNFs). This approach, characterized by its simplicity and efficiency, facilitates the amidation of nonactivated carboxylic acids in carboxymethylated cellulose nanofibrils (c-CNF). Following the optimization of reaction conditions, we successfully introduced amine-containing polymers, such as polyethylenimine and Jeffamine, onto nanofibers. This introduction significantly enhanced the physicochemical properties of the CNF-based materials, resulting in improved characteristics such as adhesiveness and thermal stability. Reaction mechanistic investigations suggested that endocyclic oxygen of cellulose finely stabilizes the transition state required for further functionalization. Notably, a nanocomposite, containing CNF and a branched low molecular weight polyethylenimine (CNF-PEI 800), was synthesized using the catalytic reaction. The composite CNF-PEI 800 was thoroughly characterized having in mind its potential application as coating biomaterial for medical implants. The resulting CNF-PEI 800 hydrogel exhibits adhesive properties, which complement the established antibacterial qualities of polyethylenimine. Furthermore, CNF-PEI 800 demonstrates its ability to support the proliferation and differentiation of primary human osteoblasts over a period of 7 days.


Assuntos
Celulose , Cloretos , Nanocompostos , Nanofibras , Celulose/química , Nanocompostos/química , Humanos , Catálise , Nanofibras/química , Cloretos/química , Compostos Férricos/química , Osteoblastos/efeitos dos fármacos , Osteoblastos/citologia , Polietilenoimina/química , Próteses e Implantes , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/síntese química
4.
J Pharm Biomed Anal ; 246: 116189, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38733763

RESUMO

Portable near-infrared (NIR) spectrophotometers have emerged as valuable tools for identifying substandard and falsified pharmaceuticals (SFPs). Integration of these devices with chemometric and machine learning models enhances their ability to provide quantitative chemical insights. However, different NIR spectrophotometer models vary in resolution, sensitivity, and responses to environmental factors such as temperature and humidity, necessitating instrument-specific libraries that hinder the wider adoption of NIR technology. This study addresses these challenges and seeks to establish a robust approach to promote the use of NIR technology in post-market pharmaceutical analysis. We developed support vector machine and partial least squares regression models based on binary mixtures of lab-made ciprofloxacin and microcrystalline cellulose, then applied the models to ciprofloxacin dosage forms that were assayed with high performance liquid chromatography (HPLC). A receiver operating characteristic (ROC) analysis was performed to set spectrophotometer independent NIR metrics to evaluate ciprofloxacin dosage forms as "meets standard," "needs HPLC assay," or "fails standard." Over 200 ciprofloxacin tablets representing 50 different brands were evaluated using spectra acquired from three types of NIR spectrophotometer with 85% of the prediction agreeing with HPLC testing. This study shows that non-brand-specific predictive models can be applied across multiple spectrophotometers for rapid screening of the conformity of pharmaceutical active ingredients to regulatory standard.


Assuntos
Ciprofloxacina , Espectroscopia de Luz Próxima ao Infravermelho , Comprimidos , Ciprofloxacina/análise , Ciprofloxacina/química , Comprimidos/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Espectroscopia de Luz Próxima ao Infravermelho/normas , Cromatografia Líquida de Alta Pressão/métodos , Calibragem , Análise dos Mínimos Quadrados , Máquina de Vetores de Suporte , Celulose/química , Celulose/análise , Medicamentos Falsificados/análise
5.
Int J Biol Macromol ; 269(Pt 1): 132052, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38704068

RESUMO

Researchers are now focusing on using the circular economy model to manufacture nanocellulose composites due to growing environmental issues related to waste management. The circular economy model offers a sustainable solution to the problem by optimizing resource efficiency and waste management by reducing waste, maintaining value over time, minimizing the use of primary resources, and creating closed loops for goods, components, and materials. With the use of the circular economy model, waste, such as industrial, agricultural, and textile waste, is used again to produce new products, which can solve waste management issues and improve resource efficiency. In order to encourage the use of circular economy ideas with a specific focus on nanocellulose composites, this review examines the concept of using circular economy, and explores ways to make nanocellulose composites from different types of waste, such as industrial, agricultural, and textile waste. Furthermore, this review investigates the application of nanocellulose composites across multiple industries. In addition, this review provides researchers useful insights of how circular economics can be applied to the development of nanocellulose composites, which have the goal of creating a flexible and environmentally friendly material that can address waste management issues and optimize resource efficiency.


Assuntos
Celulose , Celulose/química , Gerenciamento de Resíduos/métodos , Gerenciamento de Resíduos/economia , Nanocompostos/química , Nanoestruturas/química , Agricultura/economia , Agricultura/métodos
6.
Environ Pollut ; 350: 123934, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38588971

RESUMO

In the framework of a safe-by-design approach, we previously assessed the eco-safety of nanostructured cellulose sponge (CNS) leachate on sea urchin reproduction. It impaired gamete quality, gamete fertilization competence, and embryo development possibly due to the leaching of chemical additives used during the CNS synthesis process. To extend this observation and identify the component(s) that contribute to CNS ecotoxicity, in the present study, we individually screened the cytotoxic effects on sea urchin Arbacia lixula and Paracentrotus lividus gametes and embryos of the three main constituents of CNS, namely cellulose nanofibers, citric acid, and branched polyethylenimine. The study aimed to minimize any potential safety risk of these components and to obtain an eco-safe CNS. Among the three CNS constituents, branched polyethylenimine resulted in the most toxic agent. Indeed, it affected the physiology and fertilization competence of male and female gametes as well as embryo development in both sea urchin species. These results are consistent with those previously reported for CNS leachate. Moreover, the characterisation of CNS leachate confirmed the presence of detectable branched polyethylenimine in the conditioned seawater even though in a very limited amount. Altogether, these data indicate that the presence of branched polyethylenimine is a cause-effect associated with a significant risk in CNS formulations due to its leaching upon contact with seawater. Nevertheless, the suggested safety protocol consisting of consecutive leaching treatments and conditioning of CNS in seawater can successfully ameliorate the CNS ecotoxicity while maintaining the efficacy of its sorbent properties supporting potential environmental applications.


Assuntos
Celulose , Ácido Cítrico , Nanofibras , Polietilenoimina , Reprodução , Ouriços-do-Mar , Poluentes Químicos da Água , Animais , Celulose/toxicidade , Celulose/química , Polietilenoimina/toxicidade , Polietilenoimina/química , Ácido Cítrico/química , Ácido Cítrico/toxicidade , Poluentes Químicos da Água/toxicidade , Reprodução/efeitos dos fármacos , Nanofibras/toxicidade , Nanofibras/química , Feminino , Ouriços-do-Mar/efeitos dos fármacos , Masculino , Paracentrotus/efeitos dos fármacos
7.
Microsc Res Tech ; 87(8): 1933-1954, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38563156

RESUMO

The environment preservation has been an important motivation to find alternative, functional, and biodegradable materials to replace polluting petrochemicals. The production of nonbiodegradable face masks increased the concentration of microplastics in the environment, highlighting the need for sustainable alternatives, such as the use of local by-products to create efficient and eco-friendly filtering materials. Furthermore, the use of smart materials can reduce the risk of contagion and virus transmission, especially in the face of possible mutations. The development of novel materials is necessary to ensure less risk of contagion and virus transmission, as well as to preserve the environment. Taking these factors into account, 16 systems were developed with different combinations of precursor materials (holocellulose, polyaniline [ES-PANI], graphene oxide [GO], silver nanoparticles [AgNPs], and activated carbon [AC]). Adsorption tests of the spike protein showed that the systems containing GO and AC were the most efficient in the adsorption process. Similarly, plate tests conducted using the VSV-IN strain cultured in HepG2 cells showed that the system containing all phases showed the greatest reduction in viral titer method. In agreement, the biocompatibility tests showed that the compounds extracted from the systems showed low cytotoxicity or no significant cytotoxic effect in human fibroblasts. As a result, the adsorption tests of the spike protein, viral titration, and biocompatibility tests showed that systems labeled as I and J were the most efficient. In this context, the present research has significantly contributed to the technological development of antiviral systems, with improved properties and increased adsorption efficiency, reducing the viral titer and contributing efficiently to public health. In this way, these alternative materials could be employed in sensors and devices for filtering and sanitization, thus assisting in mitigating the transmission of viruses and bacteria. RESEARCH HIGHLIGHTS: Sixteen virus adsorbent systems were developed with different combinations of precursor materials (holocellulose, polyaniline (ES-PANI), graphene oxide (GO), silver nanoparticles (AgNPs), and activated carbon (AC)). The system that included all of the nanocomposites holocellulose, PANI, GO, AgNPs, and AC showed the greatest reduction in viral titration. The biocompatibility tests revealed that all systems caused only mild or moderate cytotoxicity toward human fibroblasts.


Assuntos
Grafite , Prata , Humanos , Adsorção , Grafite/química , Prata/farmacologia , Prata/química , Células Hep G2 , Nanopartículas Metálicas/química , Compostos de Anilina/farmacologia , Compostos de Anilina/química , Celulose/química , Celulose/farmacologia , Nanoestruturas/química , Carvão Vegetal/química , Carvão Vegetal/farmacologia
8.
Environ Sci Pollut Res Int ; 31(19): 28494-28506, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38561529

RESUMO

Porous carbon generated from biomass has a rich pore structure, is inexpensive, and has a lot of promise for use as a carbon material for energy storage devices. In this work, nitrogen-doped porous carbon was prepared by co-pyrolysis using bagasse as the precursor and chlorella as the nitrogen source. ZnCl2 acts as both an activator and a nitrogen fixer during activation to generate pores and reduce nitrogen loss. The thermal weight loss experiments showed that the pyrolysis temperatures of bagasse and chlorella overlap, which created the possibility for the synthesis of nitrogen-rich biochar. The optimum sample (ZBC@C-5) possessed a surface area of 1508 m2g-1 with abundant nitrogen-containing functional groups. ZBC@C-5 in the three-electrode system exhibited 244.1F/g at 0.5A/g, which was extremely close to ZBC@M made with melamine as the nitrogen source. This provides new opportunities for the use of low-cost nitrogen sources. Furthermore, the devices exhibit better voltage retention (39%) and capacitance retention (96.3%). The goal of this research is to find a low cost, and effective method for creating nitrogen-doped porous carbon materials with better electrochemical performance for highly valuable applications using bagasse and chlorella.


Assuntos
Biomassa , Carbono , Chlorella vulgaris , Nitrogênio , Pirólise , Triazinas , Nitrogênio/química , Carbono/química , Porosidade , Triazinas/química , Celulose/química
9.
Bioresour Technol ; 401: 130744, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38677384

RESUMO

Paper sludge biomass represents an underutilized feedstock rich in pulped and processed cellulose which is currently a waste stream with significant disposal cost to industry for landfilling services. Effective fractionation of the cellulose from paper sludge presents an opportunity to yield cellulose as feedstock for value-added processes. A novel approach to cellulose fractionation is the sidehill screening system, herein studied at the pilot-plant scale. Composition analysis determined ash removal and carbohydrate retention of both sidehill and high-performance benchtop screening systems. Sidehill screening resulted in greater carbohydrates retention relative to benchtop screening (90% vs 66%) and similar ash removal (95% vs 98%). Techno-economic analysis for production of sugar syrup yielded a minimum selling price of $331/metric ton of sugar syrup including disposal savings, significantly less than a commercial sugar syrup without fractionation. Sensitivity analysis showed that screening conditions played a significant role in economic feasibility for cellulosic yield and downstream processes.


Assuntos
Biomassa , Celulose , Papel , Esgotos , Projetos Piloto , Celulose/química , Fracionamento Químico
10.
ACS Appl Bio Mater ; 7(3): 1490-1500, 2024 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-38377436

RESUMO

Inflammatory disease biomarker detection has become a high priority in point-of-care diagnostic research in relation to chronic wounds, with a variety of sensor-based designs becoming available. Herein, two primary aspects of biosensor design are examined: (1) assessment of a cellulose nanofiber (CNF) matrix derived from cotton ginning byproducts as a sensor transducer surface; and (2) assessment of the relation of spacer length and morphology between the CNF cellulose backbone and peptide fluorophore as a function of sensor activity for porcine pancreatic and human neutrophil elastases. X-ray crystallography, specific surface area, and pore size analyses confirmed the suitability of CNF as a matrix for wound care diagnostics. Based upon the normalized degree of substitution, a pegylated-linker connecting CNF transducer substrate to peptide fluorophore showed the greatest fluorescence response, compared to short- and long-chain alkylated linkers.


Assuntos
Técnicas Biossensoriais , Nanofibras , Animais , Suínos , Humanos , Celulose/química , Peptídeos/química
11.
Int J Biol Macromol ; 256(Pt 1): 128432, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38013070

RESUMO

Sustainable management of walnut shell (WS) for the extraction of cellulose and preparation of cellulose-based biosorbents of iodine was carried out as a new approach to simultaneously solve the environmental challenge of agricultural solid waste and iodine-contaminated water. A rapid recyclable nitric acid treatment and NaOH-H2O2 alkaline-peroxide treatment of WS (33 % cellulose) extracted pure microcrystalline (Cac) and impure cellulose (Cal) with a 21.70 % and 47.37 % isolation yield, respectively. The techno-economic assessment of cellulose production showed a net profit of 9.02 $/kg for Cac, whereas it was estimated as negative for Cal. The simultaneous carbonization and magnetization of Cac at 550 °C resulted in an amorphous, magnetic cellulose-derived biochar (MB550Cac) with a BET specific surface area of 12.64 m2/g, decorated with scattered irregular Fe3O4 microparticles. The adsorption capacity of MB550Cac for iodine was 555.63 mg/g, which was lost only 17.45 % after six successful cycles of regeneration. Freundlich isotherm model sufficiently described the reversible iodine adsorption on the heterogenous surface. The adsorption kinetics followed the pseudo-second-order model. Further, the adsorption thermodynamics demonstrated spontaneous and favorable adsorption. These findings suggest the valorization of WS to commercially produce cellulose and MB550Cac as a sustainable, efficient biosorbent with a good application prospect in wastewater treatment.


Assuntos
Juglans , Poluentes Químicos da Água , Poluentes Químicos da Água/química , Adsorção , Peróxido de Hidrogênio , Celulose/química , Termodinâmica , Cinética , Concentração de Íons de Hidrogênio
12.
Int J Biol Macromol ; 256(Pt 1): 128186, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37979761

RESUMO

It is of tremendous economic and environmental significance to obtain a powerful adsorbent for the extraction of Gd3+ from wastewater. Adsorbents derived from cellulosic materials functionalized with specific chelators show great promise for the removal of heavy metal ions from wastewater. The selectivity of these sorbents for metal ions is, however, still rather poor. Here, we present a technique for trapping Gd3+ ions from wastewater by synthesizing Gd3+ ion-imprinted polymers based on isatinhydrazone-functionalized cellulose (Gd-ISH-CE). Not only did isatinhydrazone work as a tridentate ligand to directly provide ligand vacancies and build hierarchy pores on Gd-ISH-CE, but it also enabled cross-linking through the epichlorohydrine cross-linker thanks to its very effective NH2 functionalization. The as-prepared Gd-ISH-CE with ISH functionality shows a high adsorption capacity of 275 mg/g and a rapid equilibration time of 30 min for Gd3+ due to its plentiful binding sites and hierarchical pore structure. Furthermore, Gd-ISH-CE shows very selective capture of Gd3+ over competing ions. By integrating the benefits of ion-imprinting and chelator functionalization methodologies in an effortless manner, this study presents a practical approach to the development of superior materials for Gd3+ recovery.


Assuntos
Isatina , Poluentes Químicos da Água , Celulose/química , Águas Residuárias , Gadolínio , Ligantes , Íons/química , Adsorção , Poluentes Químicos da Água/química
13.
Food Res Int ; 173(Pt 2): 113384, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803721

RESUMO

Despite the growing demand and interest in 3D printing for food manufacturing, predicting printability of food-grade materials based on biopolymer composition and rheological properties is a significant challenge. This study developed two image-based printability assessment metrics: printed filaments' width and roughness and used these metrics to evaluate the printability of hydrogel-based food inks using response surface methodology (RSM) with regression analysis and machine learning. Rheological and compositional properties of food grade inks formulated using low-methoxyl pectin (LMP) and cellulose nanocrystals (CNC) with different ionic crosslinking densities were used as predictors of printability. RSM and linear regression showed good predictability of rheological properties based on formulation parameters but could not predict the printability metrics. For a machine learning based prediction model, the printability metrics were binarized with pre-specified thresholds and random forest classifiers were trained to predict the filament width and roughness labels, as well as the overall printability of the inks using formulation and rheological parameters. Without including formulation parameters, the models trained on rheological measurements alone were able to achieve high prediction accuracy: 82% for the width and roughness labels and 88% for the overall printability label, demonstrating the potential to predict printability of the polysaccharide inks developed in this study and to possibly generalize the models to food inks with different compositions.


Assuntos
Tinta , Polissacarídeos , Celulose/química , Alimentos , Impressão Tridimensional
14.
J Environ Manage ; 348: 119251, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37820435

RESUMO

An integrated strategy is developed to utilize all three primary components (cellulose, hemicellulose, and lignin) of lignocellulosic biomass for the coproduction of hydrocarbon fuel (5-nonanone) and bio-chemicals (furfural and high purity lignin). After biomass fractionation, (1) 5-nonanone is produced with high yield of 89% using cellulose-derived γ-valerolactone (GVL), which can potentially serve as a platform molecule for the production of liquid hydrocarbon fuels for the transportation sector; (2) furfural, a valuable platform chemical, is produced using hemicellulose; and (3) production of high-purity lignin, which can be used to produce carbon foams or battery anodes. Separation subsystems are designed to effectively recover the solvents for reuse in the conversion processes, which ultimately improves the economic feasibility of the integrated process, resulting in achieving lower minimum selling price (MSP) of $5.47 GGE-1 for 5-nonanone compared to market price. Heat pump is introduced to perform heat integration, which reduces utility requirements more than 85%. Finally, a wide range of techno-economic analysis is performed to highlight the major cost and technological drivers of the integrated process.


Assuntos
Furaldeído , Lignina , Lignina/química , Biomassa , Celulose/química , Hidrocarbonetos
15.
Biomacromolecules ; 24(11): 4672-4679, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37729475

RESUMO

Nanocellulose is isolated from cellulosic fibers and exhibits many properties that macroscale cellulose lacks. Cellulose nanocrystals (CNCs) are a subcategory of nanocellulose made of stiff, rodlike, and highly crystalline nanoparticles. Algae of the order Cladophorales are the source of the longest cellulosic nanocrystals, but manufacturing these CNCs is not well-studied. So far, most publications have focused on the applications of this material, with the basic manufacturing parameters and material properties receiving little attention. In this article, we investigate the entirety of the current manufacturing process from raw algal biomass (Cladophora glomerata) to the isolation of algal cellulose nanocrystals. Yields and cellulose purities are investigated for algal cellulose and the relevant process intermediates. Furthermore, the effect of sulfuric acid hydrolysis, which is used to convert cellulose into CNCs and ultimately determines the material properties and some of the sustainability aspects, is examined and compared to literature results on wood cellulose nanocrystals. Long (>4 µm) CNCs form a small fraction of the overall number of CNCs but are still present in measurable amounts. The results define essential material properties for algal CNCs, simplifying their future use in functional cellulosic materials.


Assuntos
Celulose , Nanopartículas , Celulose/química , Nanopartículas/química , Hidrólise
16.
Bioengineered ; 14(1): 2242124, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37548430

RESUMO

Recently, the development of sustainable and environmentally friendly biomaterials has gained the attention of researchers as potential alternatives to petroleum-based materials. Biomaterials are a promising candidate to mitigate sustainability issues due to their renewability, biodegradability, and cost-effectiveness. Thus, the purpose of this study is to explore a cost-effective biomaterial-based delivery system for delivering fertilizers to plants. To achieve this, rice straw (agro-waste) was selected as a raw material for the extraction of cellulose. The cellulose was extracted through alkali treatment (12% NaOH), followed by TEMPO-based oxidation. The cellulose nanofibers were characterized using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy, and transmission electron microscopy. In scanning electron microscopy, a loosening of the fibrillar structure in cellulose nanofibers (CNFs) was observed with a diameter of 17 ± 4 nm. The CNFs were loaded with nitrogen-based fertilizer (ammonium chloride) in 1:1, 1:2, and 2:1 (w/w) proportions. The loading was estimated through surface charge variation; in the case of the 1:1 sample, maximum reductions in surface charge were seen from -42.0 mV to -12.8 mV due to the binding of positive ammonium ions. In the release kinetics study, a controlled release pattern was observed at 1:1, which showed a 58% cumulative release of ammonium ions within 8 days. Thus, the study paves the way for value-added uses of rice straw as an alternative to the current environmentally harmful practices.


Bio-based cellulose nanofibers (CNFs) from rice straw via circular economy approach.Controlled release fertilizers for sustainable agriculture.Nanotechnology for precision agriculture and decarbonization via agricultural waste management.


Assuntos
Nanofibras , Oryza , Celulose/química , Fertilizantes , Oryza/química , Nanofibras/química , Desenvolvimento Sustentável , Preparações de Ação Retardada , Espectroscopia de Infravermelho com Transformada de Fourier , Materiais Biocompatíveis , Íons
17.
Int J Biol Macromol ; 248: 125928, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37481183

RESUMO

Cellulose aerogel (CA) is considered to be the most promising material due to its extraordinary properties like unique microstructure, porosity, large specific surface area, biodegradability, renewable nature and lightweight. Cellulosic aerogels are thus found to have potential applications in different fields especially in water purification and biomedical field. Agricultural waste based cellulose aerogels are recently getting wider attention owing to its sustainability. The synthesis methods of agri-waste based cellulose aerogels, its properties and application in different fields especially in the field of water purification are detailed in a comprehensive manner. This review tries to bring light into the commercialization of value-added products from sustainable, cheap agricultural waste material and tries to motivate young researchers.


Assuntos
Celulose , Desenvolvimento Sustentável , Celulose/química , Géis/química , Porosidade , Resíduos
18.
Int J Biol Macromol ; 242(Pt 3): 124883, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37201890

RESUMO

The light-induced processes performed by photofunctional polymer films are crucial aspects of developing integrated energy storage devices properly. Herein, we report the preparation, characterization, and study of the optical properties of a series of biobased cellulose acetate/azobenzene (CA/Az1) handleable films at different compositions. The photoswitching/back-switching behavior of the samples was investigated using varied LED irradiation sources. Additionally, poly(ethylene glycol) (PEG) was deposited onto cellulose acetate/azobenzene films to study the back-switching process's effect and nature in the fabricated films. Interestingly, the melting enthalpies of PEG before and after being irradiated with blue LED light were 2.5 mJ and 0.8 mJ, respectively. Conveniently, FTIR and UV-visible spectroscopy, thermogravimetry (TGA), contact angle, differential scanning calorimetry (DSC), polarized light microscopy (PLM), and atomic force microscopy (AFM) were used for the characterization of the sample films. Complementarily, theoretical electronic calculations provided a consistent approach to the energetic change in the dihedral angles and non-covalent interaction for the trans and cis isomer in the presence of cellulose acetate monomer. The results of this study revealed that CA/Az1 films are viable photoactive materials displaying handleability attributes with potential uses in harvesting, converting, and storing light energy.


Assuntos
Luz , Raios Ultravioleta , Celulose/química
19.
Bioresour Technol ; 382: 129166, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37210033

RESUMO

Saccharification is a pivotal step in the conversion of lignocellulose to biofuels and chemicals. In this study, crude glycerol derived from biodiesel production was used in pretreatment to facilitate efficient and clean pyrolytic saccharification of sugarcane bagasse. Delignification, demineralization, destruction of lignin-carbohydrate complex structure, and cellulose crystallinity improvement in crude glycerol pretreated biomass could enhance levoglucosan producing reactions against competitive reactions, and therefore facilitate a kinetically controlled pyrolysis with apparent activation energy increased by 2-fold. Accordingly, selective levoglucosan production (44.4%) was promoted by 6-fold whilst light oxygenates and lignin monomers were limited to <25% in bio-oil. Owing to the high-efficiency saccharification, life cycle assessment suggested that the environmental impacts of the integrated process were less than those of typical acid pretreatment and petroleum-based processes, especially on the acidification (8-fold less) and global warming potential. This study provides an environmentally benign approach to efficient biorefinery and waste management.


Assuntos
Celulose , Saccharum , Animais , Celulose/química , Lignina/química , Glicerol , Pirólise , Cinética , Biomassa , Biocombustíveis , Estágios do Ciclo de Vida , Hidrólise
20.
Chemosphere ; 329: 138552, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37003438

RESUMO

Persistent contaminants in wastewater effluent pose a significant threat to aquatic life and are one of the most significant environmental concerns of our time. Although there are a variety of traditional methods available in wastewater treatment, including adsorption, coagulation, flocculation, ion exchange, membrane filtration, co-precipitation and solvent extraction, none of these have been found to be significantly cost-effective in removing toxic pollutants from the water environment. The upfront costs of these treatment methods are extremely high, and they require the use of harmful synthetic chemicals. For this reason, the development of new technologies for the treatment and recycling of wastewater is an absolute necessity. Our way of life can be made more sustainable by the synthesis of adsorbents based on biomass, making the process less harmful to the environment. Biopolymers offer a sustainable alternative to synthetic polymers, which are manufactured by joining monomer units through covalent bonding. This review presents a detailed classification of biopolymers such as pectin, alginate, chitosan, lignin, cellulose, chitin, carrageen, certain proteins, and other microbial biomass compounds and composites, with a focus on their sources, methods of synthesis, and prospective applications in wastewater treatment. A concise summary of the extensive body of knowledge on the fate of biopolymers after adsorption is also provided. Finally, consideration is given to open questions about future developments leading to environmentally friendly and economically beneficial applications of biopolymers.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Águas Residuárias , Biopolímeros/química , Celulose/química , Quitina , Água , Poluentes Químicos da Água/química , Adsorção
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