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International Journal of Biological... Jun 2024This study explores the effectiveness of Alginate-coated nano‑iron oxide combined with copper-based MOFs (Cu-BTC@Alg/FeO) composites for the sustainable and efficient...
Sodium alginate-encapsulated nano-iron oxide coupled with copper-based MOFs (Cu-BTC@Alg/FeO): Versatile composites for eco-friendly and effective elimination of Rhodamine B dye in wastewater purification.
This study explores the effectiveness of Alginate-coated nano‑iron oxide combined with copper-based MOFs (Cu-BTC@Alg/FeO) composites for the sustainable and efficient removal of Rhodamine B (RhB) dye from wastewater through adsorption and photocatalysis. Utilizing various characterization techniques such as FTIR, XRD, SEM, and TEM, we confirmed the optimal synthesis of this composite. The composites exhibit a significant surface area of approximately 160 m g, as revealed by BET analysis, resulting in an impressive adsorption capacity of 200 mg g and a removal efficiency of 97 %. Moreover, their photocatalytic activity is highly effective, producing environmentally friendly degradation byproducts, thus underlining the sustainability of Cu-BTC@Alg/FeO composites in dye removal applications. Our investigation delves into kinetics and thermodynamics, revealing a complex adsorption mechanism influenced by both chemisorption and physisorption. Notably, the adsorption kinetics indicate equilibrium attainment within 100 min across all initial concentrations, with the pseudo-second-order kinetic model fitting the data best (R ≈ 0.999). Furthermore, adsorption isotherm models, including Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich, elucidate the adsorption behavior, with the Temkin and Dubinin-Radushkevich models showing superior accuracy compared to the Langmuir model (R ≈ 0.98 and R ≈ 0.96, respectively). Additionally, thermodynamic analysis reveals a negative Gibbs free energy value (-6.40 kJ mol), indicating the spontaneity of the adsorption process, along with positive enthalpy (+24.3 kJ mol) and entropy (+82.06 kJ mol K) values, suggesting an endothermic and disorderly process at the interface. Our comprehensive investigation provides insights into the optimal conditions for RhB adsorption onto Cu-BTC@Alg/FeO composites, highlighting their potential in wastewater treatment applications.
PubMed: 38944086
DOI: 10.1016/j.ijbiomac.2024.133498 -
International Journal of Biological... Jun 2024Nanocellulose@chitosan (nc@ch) composite beads were prepared via coagulation technique for the elimination of malachite green dye from aqueous solution. As malachite...
Nanocellulose@chitosan (nc@ch) composite beads were prepared via coagulation technique for the elimination of malachite green dye from aqueous solution. As malachite green dye is highly used in textile industries for dyeing purpose which after usage shows fatal effects to the ecosystems and human beings also. In this study the formulated nanocellulose@chitosan composite beads were characterized by Particle size analysis (PSA), Field emission scanning electron microscopy (FESEM), Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis were done to evaluate nanoparticles size distribution, morphological behaviour, functional group entities and degree of crystallinity of prepared beads. The nanocomposite beads adsorption performance was investigated for malachite green (MG) dye and BET analysis were also recorded to know about porous behaviour of the nanocomposite beads. Maximum removal of malachite green (MG) dye was found to be 72.0 mg/g for 100 ppm initial dye concentration. For accurate observations linear and non-linear modelling was done to know about the best-fitted adsorption model during the removal mechanism of dye molecules, on evaluating it has been observed that Langmuir isotherm and Freundlich isotherm show best-fitted observation in the case of linear and non-linear isotherm respectively (R = 0.96 & R = 0.957). In the case of kinetic linear models, the data was well fitted with pseudo-second-order showing chemosorption mechanism (R = 0.999), and in the case of non-linear kinetic model pseudo first order showed good fit showing physisorption mechanism during adsorption (R = 0.999). The thermodynamic study showed positive values for ΔH° and ΔS° throughout the adsorption process respectively, implying an endothermic behaviour. In view of cost effectiveness, desorption or regeneration study was done and it was showed that after the 5th cycle, the removal tendency had decreased from 48 to 38 % for 20-100 ppm dye solution accordingly. Thus, nanocomposite beads prepared by the coagulation method seem to be a suitable candidate for dye removal from synthetic wastewater and may have potential to be used in small scale textile industries for real wastewater treatment.
PubMed: 38944080
DOI: 10.1016/j.ijbiomac.2024.133512 -
International Journal of Biological... Jun 2024We study the effect of electrolytes on the stability in aqueous media of spherical lignin particles (LP) and its relevance to Pickering emulsion stabilization. Factors...
We study the effect of electrolytes on the stability in aqueous media of spherical lignin particles (LP) and its relevance to Pickering emulsion stabilization. Factors considered included the role of ionic strength on morphology development, LP size distribution, surface charge, interfacial adsorption, colloidal and wetting behaviors. Stable emulsions are formed at salt concentrations as low as 50 mM, with the highest stability observed at a critical concentration (400 mM). We show salt-induced destabilization of LP aqueous dispersions at an ionic strength >400 mM. At this critical concentration LP flocculation takes place and particulate networks are formed. This has a profound consequence on the stability of LP-stabilized Pickering emulsions, affecting rheology and long-term stability. The results along with quartz microgravimetry and confocal microscopy observations suggest a possible mechanism for stabilization that considers the interfacial adsorption of LP at oil/water interfaces. The often-unwanted colloidal LP destabilization in water ensues remarkably stable Pickering emulsions by the effect of network formation.
PubMed: 38944069
DOI: 10.1016/j.ijbiomac.2024.133504 -
Food Chemistry Jun 2024The accurate determination of polar cationic pesticides in food poses a challenge due to their high polarity and trace levels in complex matrices. This study...
The accurate determination of polar cationic pesticides in food poses a challenge due to their high polarity and trace levels in complex matrices. This study hypothesized that the use of halloysite nanotubes (HNTs) can significantly enhance the extraction efficiency and sensitivity of these analytes because of their rich hydroxyl groups and cation exchange sites. Therefore, we chemically incorporated HNTs with organic polymer monoliths for in-tube solid-phase microextraction (SPME). This novel hybrid monolith extended service life, improved adsorption capacity, and exhibited excellent extraction performance for polar cationic pesticides. Based on these advancements, a robust and sensitive in-tube SPME-HILIC-MS/MS method was constructed to determine trace levels of polar cationic pesticides in complex food matrices. The method achieved limits of detection of 1.9, 2.1, and 0.1 μg/kg for maleic hydrazide, amitrole, and cyromazine, respectively. The spiked recoveries in five food samples ranged from 80.2 to 100.8%, with relative standard deviations below 10.7%.
PubMed: 38943962
DOI: 10.1016/j.foodchem.2024.140205 -
Bimetallic metal-organic framework aerogels supported by aramid nanofibers for efficient CO capture.Journal of Colloid and Interface Science Jun 2024The excessive CO emission has gained global attentions due to its potential effects on climate change, plant nutrition deterioration, and human health and safety....
The excessive CO emission has gained global attentions due to its potential effects on climate change, plant nutrition deterioration, and human health and safety. Metal-organic frameworks (MOFs) featured with high specific surface area, adjustable pore size, and tailorable morphology have been widely applied for CO capture. However, some drawbacks of poor mechanical stability and uneven distribution of mesopores limit their further applications. Herein, we demonstrate a one-step synthesis of bimetallic center framework (OSSBCF) and pore reconstruction (PRC) strategy to prepare the hierarchical porous Zn/Co-ZIF@ANF aerogels. This unique design achieves the construction of efficient gas transfer channels and creates massive micropores with abundant Lewis basic adsorption sites. Benefiting from theses merits, the bimetallic Zn/Co-ZIF@ANF aerogels demonstrate high MOFs loading mass of 47.51 wt%, high specific surface area of 686.39 mg, and large porosity of 99.31 %. Moreover, the bimetallic Zn/Co-ZIF@ANF aerogels exhibit an enhanced CO adsorption capacity of 5.99 mmol/g and CO/N adsorption selectivity of 35 at 25 °C and 1 bar. The CO capacity of bimetallic Zn/Co-ZIF@ANF aerogels keep up to 95.19 % after ten cycles of CO adsorption, indicating the excellent long-term recycle stability. Therefore, this study provides a promising strategy to engineer hierarchical porous bimetallic MOF aerogels toward practical CO capture.
PubMed: 38943914
DOI: 10.1016/j.jcis.2024.06.125 -
Journal of Hazardous Materials Jun 2024Highly-stable heavy metal ions (HMIs) appear long-term damage, while the existing remediation strategies struggle to effectively remove a variety of oppositely charged...
Highly-stable heavy metal ions (HMIs) appear long-term damage, while the existing remediation strategies struggle to effectively remove a variety of oppositely charged HMIs without releasing toxic substances. Here we construct an iron-copper primary battery-based nanocomposite, with photo-induced protonation effect, for effectively consolidating broad-spectrum HMIs. In FCPBN, Fe/Cu cell acts as the reaction impetus, and functional graphene oxide modified by carboxyl and UV-induced protonated 2-nitrobenzaldehyde serves as an auxiliary platform. Due to the groups and built-in electric fields under UV stimuli, FCPBN exhibits excellent affinity for ions, with a maximum adsorption rate constant of 974.26 g∙mg∙min and facilitated electrons transfer, assisting to reduce 9 HMIs including CrO, AsO, Cd in water from 0.03 to 3.89 ppb. The cost-efficiency, stability and collectability of the FCPBN during remediation, and the beneficial effects on polluted soil and the beings further demonstrate the splendid remediation performance without secondary pollution. This work is expected to remove multi-HMIs thoroughly and sustainably, which tackles an environmental application challenge.
PubMed: 38943880
DOI: 10.1016/j.jhazmat.2024.135066 -
Spectrochimica Acta. Part A, Molecular... Jun 2024The present study explores the kitchen waste okra peels derived synthesis of nitrogen doped carbon dots (N-CDs) via simple carbonization followed by reflux method. The...
Okra peel-derived nitrogen-doped carbon dots: Eco-friendly synthesis and multi-functional applications in heavy metal ion sensing, nitro compound detection and environmental remediation.
The present study explores the kitchen waste okra peels derived synthesis of nitrogen doped carbon dots (N-CDs) via simple carbonization followed by reflux method. The synthesized N-CDs was characterized using, TEM, XPS, FTIR, XRD, Raman, UV-Visible and Fluorescence Spectroscopy. The N-CDs emits bright blue emission at 420 nm with 12 % of quantum yield as well as it follows excitation dependent emission. Further, the N-CDs were employed as a fluorescence sensor for detection of hazardous metal ions and nitro compounds. Among various metal ions and nitro compounds, the N-CDs shows fluorescence quenching response towards Cr, and Mn metal ions as well as 4-nitroaniline (4-NA) and picric acid (PA) with significant hypsochromic and bathochromic shift for Mn, 4-NA and PA respectively. The developed fluorescent probe shows relatively low limit of detection (LOD) of 1.46 µg/mL, 1.05 µg/mL, 2.1 µg/mL and 2.2 µg/mL for the above analytes respectively. The N-CDs did not show any significant interference with coexisting ions and successfully applied for real water sample analysis. In addition, circular economy approach was employed for adsorption of dyes by reactivating leftover waste carbon residue which was obtained after reflux. Thus, the kitchen waste valorization and circular economy approach based N-CDs have potential applications in the field of detection of emerging pollutants, and environmental remediation.
PubMed: 38943759
DOI: 10.1016/j.saa.2024.124659 -
Journal of Environmental Management Jun 2024The impact of NaOH-modified biochar on the release of NH and HS from laying hens' manure was examined for 44 days, using a small-scale simulated aerobic composting...
The impact of NaOH-modified biochar on the release of NH and HS from laying hens' manure was examined for 44 days, using a small-scale simulated aerobic composting system. The findings revealed that the NaOH-modified biochar reduced NH and HS emissions by 40.63% and 77.78%, respectively, compared to the control group. Moreover, the emissions of HS were significantly lower than those of the unmodified biochar group (p < 0.05). The increased specific surface area and microporous structure of the biochar, as well as the higher content of alkaline and oxygenated functional groups, were found to facilitate the adsorption of NH and HS. This enhanced adsorption capability was the primary reason for the significant reduction in NH emissions. Furthermore, during the high-temperature phase of composting, there was a notable alteration in the microbial community. The abundance of Limnochordaceae, Savagea, and IMCC26207 increased significantly which aided in the conversion of HS to stable sulfate. These microorganisms also influenced the abundance of functional genes involved in sulfur metabolism, thereby inhibiting cysteine synthesis, along with the decomposition and conversion of sulfate to sulfite. This led to a significant decrease in HS emissions. This study provides valuable data for the selection of deodorizers in the composting process of egg-laying hens. The results have significant implications for the application of NaOH-modified biochar for odor reduction in aerobic composting processes.
PubMed: 38943752
DOI: 10.1016/j.jenvman.2024.121634 -
Journal of Environmental Management Jun 2024Sustainable management of critical raw materials is of paramount importance to ensure a steady supply and reduce environmental impact. The application of newly...
Sustainable management of critical raw materials is of paramount importance to ensure a steady supply and reduce environmental impact. The application of newly synthesized and environmentally friendly ALG@CS material as a bio-adsorbent for the effective rare earth elements removal from aqueous solution has been presented. The synthesized material underwent FTIR, XPS, EDX, and SEM analysis to determine its suitability for metal uptake. To evaluate the adsorption capacity of ALG@CS for rare earth elements several factors were taken into consideration. These factors included alginate:chitosan ratios, bead size, pH level, composite mass, interaction time, metal ion concentration, and temperature, being all varied during the batch mode evaluation process. Under the optimal conditions, the maximum adsorption capacities were found to be 145.90 mg La(III)/g, 168.44 mg Ce(III)/g, 132.51 mg Pr(III)/g, 128.40 mg Nd(III)/g, 154.36 mg Sm(III)/g, and 165.10 mg Ho(III)/g. The equilibrium data fits well with non-linear three-parameter Sips and Redlich-Peterson isotherm models. The PSO model finds the highest process suitability. The synthesized ALG@CS bio-adsorbent showed excellent regenerative capacity in ten cycles, making it a suitable adsorbent for rare earth elements uptake. The unique bio-adsorbents combination allows for efficient critical raw materials adsorption providing a promising solution for their recovery and recycling.
PubMed: 38943744
DOI: 10.1016/j.jenvman.2024.121609 -
Analytical Chemistry Jun 2024Detecting harmful pathogens in food is not only a crucial aspect of food quality management but also an effective way to ensure public health. In this paper, a complete...
Detecting harmful pathogens in food is not only a crucial aspect of food quality management but also an effective way to ensure public health. In this paper, a complete nuclear magnetic resonance biosensor based on a novel gadolinium (Gd)-targeting molecular probe was developed for the detection of Salmonella in milk. First, streptavidin was conjugated to the activated macromolecular polyaspartic acid (PASP) via an amide reaction to generate SA-PASP. Subsequently, the strong chelating and adsorption properties of PASP toward the lanthanide metal gadolinium ions were exploited to generate the magnetic complex (SA-PASP-Gd). Finally, the magnetic complex was linked to biotinylated antibodies to obtain the bioprobe and achieve the capture of Salmonella. Under optimal experimental conditions, the sensor we have constructed can achieve a rapid detection of Salmonella within 1.5 h, with a detection limit of 7.1 × 10 cfu mL.
PubMed: 38943569
DOI: 10.1021/acs.analchem.4c01265