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Azo compounds, particularly azo dyes, are widely used but pose significant environmental risks due to their persistence and potential to form carcinogenic by-products. Advanced oxidation processes (AOPs) are effective in degrading these stubborn compounds, with Oxone activation being a particularly promising method. In this study, a unique nanohybrid material, raspberry-like CuCo alloy embedded carbon (RCCC), is facilely fabricated using CuCo-glycerate (Gly) as a template. With the incorporation of Cu into Co, RCCC is essentially different from its analogue derived from Co-Gly in the absence of Cu, affording a popcorn-like Co embedded on carbon (PCoC). RCCC exhibits a unique morphology, featuring a hollow spherical layer covered by nanoscale beads composed of CuCo alloy distributed over carbon. Therefore, RCCC significantly outperforms PCoC and Co3O4 for activating Oxone to degrade the toxic azo contaminant, Azorubin S (AS), in terms of efficiency and kinetics. Furthermore, RCCC remains highly effective in environments with high NaCl concentrations and can be efficiently reused across multiple cycles. Besides, RCCC also leads to the considerably lower Ea of AS degradation than the reported Ea values by other catalysts. More importantly, the contribution of incorporating Cu with Co as CuCo alloy in RCCC is also elucidated using the Density-Function-Theory (DFT) calculation and synergetic effect of Cu and Co in CuCo contributes to enhance Oxone activation, and boosts generation of SO4â¢-and â¢OH. The decomposition pathway of AS by RCCC + Oxone is also comprehensively investigated by studying the Fukui indices of AS and a series of its degradation by-products using the DFT calculation. In accordance to the toxicity assessment, RCCC + Oxone also considerably reduces acute and chronic toxicities to lower potential environmental impact. These results ensure that RCCC would be an advantageous catalyst for Oxone activation to degrade AS in water.
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Renewable chemicals, which are made from renewable resources such as biomass, have attracted significant interest as substitutes for natural gas- or petroleum-derived chemicals to enhance the sustainability of the chemical and petrochemical industries. Polybutylene adipate terephthalate (PBAT), which is a copolyester of 1,4-butanediol (1,4-BDO), adipic acid (AA), and dimethyl terephthalate (DMT) or terephthalic acid (TPA), has garnered significant interest as a biodegradable polymer. This study assesses the non-biological production of PBAT monomers from biomass feedstocks via heterogeneous catalytic reactions. The biomass-based catalytic routes to each monomer are analyzed and compared to conventional routes. Although no fully commercialized catalytic processes for direct conversion of biomass into 1,4-BDO, AA, DMT, and TPA are available, emerging and promising catalytic routes have been proposed. The proposed biomass-based catalytic pathways toward 1,4-BDO, AA, DMT, and TPA are not yet fully competitive with conventional fossil fuel-based pathways mainly due to high feedstock prices and the existence of other alternatives. However, given continuous technological advances in the renewable production of PBAT monomers, bio-based PBAT should be economically viable in the near future.
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White Roman goose (Anser anser domesticus) feathers, comprised of oriented conical barbules, are coated with gland-secreted preening oils to maintain a long-term nonwetting performance for surface swimming. The geese are accustomed to combing their plumages with flat bills in case they are contaminated with oleophilic substances, during which the amphiphilic saliva spread over the barbules greatly impairs their surface hydrophobicities and allows the trapped contaminants to be anisotropically self-cleaned by water flows. Particularly, the superhydrophobic behaviors of the goose feathers are recovered as well. Bioinspired by the switchable anisotropic self-cleaning functionality of white Roman geese, superhydrophobic unidirectionally inclined conical structures are engineered through the integration of a scalable colloidal self-assembly technology and a colloidal lithographic approach. The dependence of directional sliding properties on the shape, inclination angle, and size of conical structures is systematically investigated in this research. Moreover, their switchable anisotropic self-cleaning functionalities are demonstrated by Sudan blue II/water (0.01%) separation performances. The white Roman goose feather-inspired coatings undoubtedly offer a new concept for developing innovative applications that require directional transportation and the collection of liquids.
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Plumas , Gansos , Animais , Plumas/química , Anisotropia , Interações Hidrofóbicas e Hidrofílicas , Propriedades de Superfície , Coloides/químicaRESUMO
This study explored the treatment of Leucomalachite Green (LMG) solutions using an electron beam and sodium persulfate (Na2S2O8), employing Box-Behnken design (BBD) to optimize operational variables such as absorbed dose, initial pH and Na2S2O8 concentration. The findings highlighted an optimal absorbed dose of 4.5 kGy, a Na2S2O8 concentration of 1.0 mM, and an initial pH of 6, leading to a remarkable 97.77% removal of LMG. The adjusted R2 for the model indicated a close match of 1.4% between predicted and actual outcomes under these optimized conditions, affirming the quadratic model's suitability for predicting the LMG removal process using combined EB and Na2S2O8. To assess the environmental impact of the LMG treatment, the study applied SimaPro 9.4 with the TRACI tool, examining ten distinct environmental impact categories. The results unveiled that deionized water and Na2S2O8 exhibited a notable impact on global warming (GW) and ecotoxicity (ET) in controlled laboratory settings. Furthermore, a comparative analysis of four scenarios shed light on the environmental implications of different energy sources. Notably, electricity generated from waste incineration demonstrated a substantial influence on all environmental indicators. In contrast, natural gas emerged as the cleanest source for electricity generation, offering a promising avenue for reducing environmental impacts. This study presents a practical method for addressing dye contaminants through the employment of EB in conjunction with Na2S2O8, with potential implications for broader applications.
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The escalation of global water pollution due to emerging pollutants has gained significant attention. To address this issue, catalytic peroxymonosulfate (PMS) activation technology has emerged as a promising treatment approach for effectively decontaminating a wide range of pollutants. Recently, modified biochar has become an increasingly attractive as PMS activator. Metal-heteroatom-co-doped biochar (MH-BC) has emerged as a promising catalyst that can provide enhanced performance over heteroatom-doped and metal-doped biochar due to the synergism between metal and heteroatom in promoting PMS activation. Therefore, this review aims to discuss the fabrication pathways (i.e., internal vs external doping and pre-vs post-modification) and key parameters (i.e., source of precursors, synthesis methods, and synthesis conditions) affecting the performance of MH-BC as PMS activator. Subsequently, an overview of all the possible PMS activation pathways by MH-BC is provided. Subsequently, Also, the detection, identification, and quantification of several reactive species (such as, â¢OH, SO4â¢-, O2â¢-, 1O2, and high valent oxo species) generated in the catalytic PMS system by MH-BC are also evaluated. Lastly, the underlying challenges associated with poor stability, the lack of understanding regarding the interaction between metal and heteroatom during PMS activation and quantification of radicals in multi-ROS system are also deliberated.
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Carvão Vegetal , Recuperação e Remediação Ambiental , Peróxidos , Carvão Vegetal/química , Peróxidos/química , Recuperação e Remediação Ambiental/métodos , Catálise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Metais/químicaRESUMO
This study aimed to investigate bone char's physicochemical transformations through co-torrefaction and co-pyrolysis processes with biomass. Additionally, it aimed to analyze the carbon sequestration process during co-torrefaction of bone and biomass and optimize the process parameters of co-torrefaction. Finally, the study sought to evaluate the arsenic sorption capacity of both torrefied and co-torrefied bone char. Bone and biomass co-torrefaction was conducted at 175 °C-300 °C. An orthogonal array of Taguchi techniques and artificial neural networks (ANN) were employed to investigate the influence of various torrefaction parameters on carbon dioxide sequestration within torrefied bone char. A co-torrefied bone char, torrefied at a reaction temperature of 300 °C, a heating rate of 15 °C·min-1, and mixed with 5 g m of biomass (wood dust), was selected for the arsenic (III) sorption experiment due to its elevated carbonate content. The results revealed a higher carbonate fraction (21%) in co-torrefied bone char at 300 °C compared to co-pyrolyzed bone char (500-700 °C). Taguchi and artificial neural network (ANN) analyses indicated that the relative impact of process factors on carbonate substitution in bone char followed the order of co-torrefaction temperature (38.8%) > heating rate (31.06%) > addition of wood biomass (30.1%). Co-torrefied bone chars at 300 °C exhibited a sorption capacity of approximately 3 mg g-1, surpassing values observed for pyrolyzed bone chars at 900 °C in the literature. The findings suggest that co-torrefied bone char could serve effectively as a sorbent in filters for wastewater treatment and potentially fulfill roles such as a remediation agent, pH stabilizer, or valuable source of biofertilizer in agricultural applications.
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Arsênio , Biomassa , Carvão Vegetal , Águas Residuárias , Poluentes Químicos da Água , Arsênio/análise , Arsênio/química , Carvão Vegetal/química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Adsorção , Osso e Ossos/química , Redes Neurais de Computação , Animais , PiróliseRESUMO
In this study, CoCr layered double hydroxide material (CoCr-LDH) was prepared and used as an effective catalyst for peroxymonosulfate (PMS) activation to degrade organics in water. The prepared CoCr-LDH material had a crystalline structure and relatively porous structure, as determined by various surface analyses. In Rhodamine B (RhB) removal, the most outstanding PMS activation ability belongs to the material with a Co:Cr molar ratio of 2:1. The removal of RhB follows pseudo-first-order kinetics (R2 > 0.99) with an activation energy of 38.23 kJ/mol and efficiency of 98% after 7 min of treatment, and the total organic carbon of the solution reduced 47.2% after 10 min. The activation and oxidation mechanisms were proposed and the RhB degradation pathways were suggested with the key contribution of O2â¢- and 1O2. Notably, CoCr-LDH can activate PMS over a wide pH range of 4 - 9, and apply to a wide range of organic pollutants and aqueous environments. The material has high stability and good recovery, which can be reused for 5 cycles with a stable efficiency of above 88%, suggesting a high potential for practical recalcitrant water treatment via PMS activation by heterogeneous catalysts.
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Peróxidos , Poluentes Químicos da Água , Purificação da Água , Poluentes Químicos da Água/química , Peróxidos/química , Purificação da Água/métodos , Rodaminas/química , Cinética , Oxirredução , CatáliseRESUMO
Recently, carbon quantum dots (CQDs) have become popular because of their simple synthesis and potential applications. Although CQDs have high biocompatibility, their biotoxicity must be verified to reduce the possible risks associated with large-scale application. In this study, the hepatotoxicity of three CQD types, namely diammonium citrate (AC)-based (CQDs-AC), spermidine trihydrochloride (Spd)-based (CQDs-Spd), and AC- and Spd-based CQDs (CQDs-AC/Spd), were evaluated in vivo and in vitro. It was observed in vivo that CQDs-Spd and CQDs-AC/Spd, but not CQDs-AC, caused histopathological damage, including liver steatosis and mild mixed inflammatory cell infiltration; however, reduced liver function was only observed in CQD-Spd-treated mice. The in vitro results revealed that only CQDs-Spd significantly decreased the number of viable HepG2 cells (NADH depletion) and induced oxidative stress (heme oxygenase-1 activation) after 24 h of exposure, which promoted inflammatory factor secretion (NF-κB activation). Additionally, decreasing zonula occludens-2 and α1-antitrypsin protein expression in HepG2 cells suggested that CQD-Spd exposure increases the risk of liver diseases. Our results revealed that CQDs-Spd had greater hepatotoxic potential than CQDs-AC and CQDs-AC/Spd, which might be attributable to their high positive surface charge. Overall, the risk of CQD-induced hepatotoxic risk must be considered when applying positively charged CQDs.
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Doença Hepática Induzida por Substâncias e Drogas , Pontos Quânticos , Camundongos , Animais , Humanos , Pontos Quânticos/toxicidade , Carbono/farmacologia , Espermidina , Células Hep G2 , Doença Hepática Induzida por Substâncias e Drogas/etiologiaRESUMO
Using edible lipids for biodiesel production has been criticized, causing biodiesel production from inedible food resources to be desirable. Lipid extraction must be prioritized to produce biodiesel using an acid/base-catalyzed transesterification process, but this conversion process suffers from technical reliability. Therefore, this study introduced non-catalytic conversion of oil-bearing biomass into biodiesel. Apricot seeds were used as a model compound (oil content 44.3 wt%). The non-catalytic transesterification of apricot seed oil recovered 98.28 wt% biodiesel at 360 °C for 1 min, while alkali-catalysis of apricot seed oil recovered 91.84 wt% at 63 °C for 60 min. The direct conversion of apricot seeds into biodiesel was attempted. The trends in the yields of biodiesel from apricot seeds and seed oil obtained by non-catalytic transesterification as a function of reaction temperature were similar. The yield of biodiesel from apricot seed was 43.06 wt%, suggesting that 97.20 wt% of lipids were converted into biodiesel.
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Prunus armeniaca , Biocombustíveis , Reprodutibilidade dos Testes , Esterificação , Ácidos Graxos , Sementes , Óleos de Plantas , CatáliseRESUMO
The management of plastic waste (PW) has become an indispensable worldwide issue because of the enhanced accumulation and environmental impacts of these waste materials. Thermo-catalytic pyrolysis has been proposed as an emerging technology for the valorization of PW into value-added liquid fuels. This review provides a comprehensive investigation of the latest advances in thermo-catalytic pyrolysis of PW for liquid fuel generation, by emphasizing polyethylene, polypropylene, and polystyrene. To this end, the current strategies of PW management are summarized. The various parameters affecting the thermal pyrolysis of PW (e.g., temperature, residence time, heating rate, pyrolysis medium, and plastic type) are discussed, highlighting their significant influence on feed reactivity, product yield, and carbon number distribution of the pyrolysis process. Optimizing these parameters in the pyrolysis process can ensure highly efficient energy recovery from PW. In comparison with non-catalytic PW pyrolysis, catalytic pyrolysis of PW is considered by discussing mechanisms, reaction pathways, and the performance of various catalysts. It is established that the introduction of either acid or base catalysts shifts PW pyrolysis from the conventional free radical mechanism towards the carbonium ion mechanism, altering its kinetics and pathways. This review also provides an overview of PW pyrolysis practicality for scaling up by describing techno-economic challenges and opportunities, environmental considerations, and presenting future outlooks in this field. Overall, via investigation of the recent research findings, this paper offers valuable insights into the potential of thermo-catalytic pyrolysis as an emerging strategy for PW management and the production of liquid fuels, while also highlighting avenues for further exploration and development.
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Poliestirenos , Pirólise , Polienos , Polietileno , PlásticosRESUMO
Owing to the ever-increasing generation of plastic waste, the need to develop environmentally friendly disposal methods has increased. This study explored the potential of waste plastic straw to generate valuable light olefins and monocyclic aromatic hydrocarbons (MAHs) via catalytic pyrolysis using high-silica zeolite-based catalysts. HZSM-5 (SiO2/Al2O3:200) exhibited superior performance, yielding more light olefins (49.8 wt%) and a higher MAH content than Hbeta (300). This was attributed to the increased acidity and proper shape selectivity. HZSM-5 displayed better coking resistance (0.7 wt%) than Hbeta (4.4 wt%) by impeding secondary reactions, limiting coke precursor formation. The use of HZSM-5 (80) resulted in higher MAHs and lower light olefins than HZSM-5 (200) because of its higher acidity. Incorporation of Co into HZSM-5 (200) marginally lowered light olefin yield (to 44.0 wt%) while notably enhancing MAH production and boosting propene selectivity within the olefin composition. These observations are attributed to the well-balanced coexistence of Lewis and Brønsted acid sites, which stimulated the carbonium ion mechanism and induced H-transfer, cyclization, Diels-alder, and dehydrogenation reactions. The catalytic pyrolysis of plastic straw over high-silica and metal-loaded HZSM-5 catalysts has been suggested as an efficient and sustainable method for transforming plastic waste materials into valuable light olefins and MAHs.
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Hidrocarbonetos Aromáticos , Zeolitas , Dióxido de Silício , Pirólise , Temperatura Alta , Biomassa , Alcenos , Catálise , HidrocarbonetosRESUMO
To date, intensive emphasis is required to develop advanced postharvest technologies to ensure food security, increase nutrition, and improve farmers toward cleaner production. How to effectively degrade the harmful gaseous ethylene (C2H4) biosynthesis, which distributes heavy losses of fresh-cut fruits and vegetables, has received considerable attention. Among various advanced techniques, photocatalytic degradation of biological C2H4 is proposed as the most promising method to solve this issue. In this context, the recent studies on the photodegradation of C2H4 have been critically summarized and highlighted. Many photocatalysts, including TiO2-based and non-TiO2-based (metal oxides (ZnO, WO3, Ga2O3), molybdates (ß-Ag2MoO4), phosphides (Ag3PO4), perovskite oxides (Bi2WO6)) nanomaterials, have been revealed with credible performance results. Also, varying reaction parameters to optimize the photocatalytic degradation efficacy in the literature are summarized. We also discussed the current status, challenges, and prospects for enhanced photodegradation of C2H4 in this study. The efficacy and economics of photodegradation have played an essential role in selecting a particular type of photocatalyst. Although many efforts have been made, significant improvements are still required for photocatalysis. In this work, we have also successfully suggested some strategies to further promote this concept for controlling and degrading plant-generated C2H4 in fruit and vegetable postharvest in a sustainable and economically feasible manner.
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Even though transition metals can activate Oxone to degrade toxic contaminants, bimetallic materials possess higher catalytic activities because of synergistic effects, making them more attractive for Oxone activation. Herein, nanoscale CuCo-bearing N-doped carbon (CuCoNC) can be designed to afford a hollow structure as well as CuCo species by adopting cobaltic metal organic frameworks as a template. In contrast to Co-bearing N-doped carbon (CoNC), which lacks the Cu dopant, CuCo alloy nanoparticles (NPs) are contained by the Cu dopant within the carbonaceous matrix, giving CuCoNC more prominent electrochemical properties and larger porous structures and highly nitrogen moieties. CuCoNC, as a result, has a significantly higher capability compared to CoNC and Co3O4 NPs, for Oxone activation to degrade a toxic contaminant, Rhodamine B (RDMB). Furthermore, CuCoNC+Oxone has a smaller activation energy for RDMB elimination and maintains its superior effectiveness for removing RDMB in various water conditions. The computational chemistry insights have revealed the RDMB degradation mechanism. This study reveals that CuCoNC is a useful activator for Oxone to eliminate RDMB.
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Due to their diverse and unique physical properties, miktoarm star copolymers (µ-SCPs) have garnered significant attention. In our study, we employed α-monobomoisobutyryl-terminated polydimethylsiloxane (PDMS-Br) to carry out styrenics-assisted atom transfer radical coupling (SA ATRC) in the presence of 4-vinylbenzyl alcohol (VBA) at 0 °C. By achieving high coupling efficiency (χc = 0.95), we obtained mid-chain functionalized PDMS-VBAm-PDMS polymers with benzylic alcohols. Interestingly, matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) analysis revealed the insertion of only two VBA coupling agents (m = 2). Subsequently, the PDMS-VBA2-PDMS products underwent mid-chain extensions using ε-caprolactone (ε-CL) through ring-opening polymerization (ROP) with an efficient organo-catalyst at 40 °C, resulting in the synthesis of novel (PDMS)2-µ-(PCL)2 µ-SCPs. Eventually, novel (PDMS)2-µ-(PCL)2 µ-SCPs were obtained. The obtained PDMS-µ-PCL µ-SCPs were further subjected to examination of their solid-state self-assembly through small-angle X-ray scattering (SAXS) experiments. Notably, various nanostructures, including lamellae and hexagonally packed cylinders, were observed with a periodic size of approximately 15 nm. As a result, we successfully developed a simple and effective reaction combination (Ð) strategy (i.e., SA ATRC-Ð-ROP) for the synthesis of well-defined PDMS-µ-PCL µ-SCPs. This approach may open up new possibilities for fabricating nanostructures from siloxane-based materials.
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Odor is a critical environmental problem that negatively affects people's quality of life. Wastewater treatment plants (WWTPs) often emit various odorous compounds, such as ammonia, sulfur dioxide, and organosulfur. Abatement of odor emissions from WWTPs using biochar may contribute to achieving carbon neutrality due to the carbon negative nature, CO2 sorption, and negative priming effects of biochar. Biochar has a high specific surface area and microporous structure with appropriate activation, which is suitable for sorption purposes. Various research directions have been proposed to determine the biochar removal efficiency for different odorants released from WWTPs. According to the literature survey, the pre- and post-treatments (e.g., thermal treatment, chemical treatment, and metal impregnation) of biochar could enhance the removal capacity for the odorants emitted from WWTPs at comparable conditions, compared to unmodified biochar. The feedstock and production condition (particularly, pyrolysis temperature) of a biochar and initial concentration of an odorant markedly affect the biochar's odorant removal capacity and efficiency. Moreover, different adsorption systems for the removal of odorants emitted from WWTPs follow different adsorption models. Further research is required to establish the practical use of biochar for the mitigation of odors released from WWTPs.
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Pine wastes, including pine needles, cones, and wood, are abundantly produced as an agroforestry by-product globally and have shown tremendous potential for biochar production. Various thermochemical conversion technologies have exhibited promising results in converting pine wastes to biochar, displaying impressive performance. Hence, this review paper aims to investigate the possibilities and recent technological advancements for synthesizing biochar from pine waste. Furthermore, it explores techniques for enhancing the properties of biochar and its integrated applications in various fields, such as soil and water remediation, carbon sequestration, battery capacitor synthesis, and bio-coal production. Finally, the paper sheds light on the limitations of current strategies, emphasizing the need for further research and study to address the challenges in pine waste-based biochar synthesis. By promoting sustainable and effective utilization of pine wastes, this review contributes to environmental conservation and resource management.
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Carvão Vegetal , Pinus , Carvão Vegetal/química , Solo/química , MadeiraRESUMO
Optical coatings with reversibly tunable antireflective characteristics hold a tremendous potential for next generation optical energy-related applications. Bioinpsired by the camouflage behavior of small yellow leafhoppers, silica hollow sphere/shape memory polymer composites are self-assembled using a non-lithography-based approach. The average visible transmittance of the as-patterned hierarchical structure array-covered substrate is increased by ca. 6.3% at normal incident, and even improved by more than 20% for an incident angle of 75°. Interestingly, the broadband omnidirectional antireflection performance can be reversibly erased and recovered by applying external stimuli under ambient conditions. To gain a better understanding, its reversibility, mechanical robustness, and the structure-shape effect on the antireflective properties are systematically investigated in this research.
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The Fenton-like reaction is a promising organic wastewater treatment reaction among advanced oxidation processes (AOP), which has emerged to replace the conventional Fenton reaction. Recycled construction and demolition waste (CDW), which is porous and rich in iron, manganese, and magnesium, can be reused as a Fenton-like catalyst. This study proposes an AOP wastewater treatment strategy using recycled porous CDW mixed with hydrogen peroxide (H2O2) to decompose methylene blue (MB) wastewater. According to the apparent first-order rate (Kapp) of 10 ppm MB adsorption, CDW-3, having the highest specific surface area, also has the highest Kapp of 0.23 min-1 g-1. The optimized conditions recommended by the Taguchi method include a 0.3 g mL-1 CDW-3 concentration, a 0.254 g mL-1 H2O2 concentration, and 10 ppm MB, resulting in an about 2.01 min-1Kapp value. In addition, MB concentration is observed as the most influential factor for Kapp, which decreases with increasing MB concentration and is about 0.62 min-1 at 1000 ppm MB. Repeating the Fenton-like reaction five times at 100 p.m. MB using the same CDW-3, the Kapp is about 0.64 min-1, which is 86% of the initial run. The synergistic effect index (ξ) is defined to quantify the level of interaction between CDW and H2O2, which produces free radicals during the Fenton-like process. The ξ of CDW-3 is about 2.16. Overall, it is demonstrated that CDW is a promising catalyst for Fenton-like reactions, and the synergistic effect index (ξ) can be used as a reference index to evaluate the catalytic generation of free radicals between the catalyst and H2O2.
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Poluentes Ambientais , Peróxido de Hidrogênio , Águas Residuárias , Ferro , Oxirredução , Azul de MetilenoRESUMO
In the present work, a novel Fe3O4-GLP@CAB was successfully synthesized via a co-precipitation procedure and applied for the removal of methylene blue (MB) from aqueous environment. The structural and physicochemical characteristics of the as-prepared materials were explored using a variety of characterization methods, including pHPZC, XRD, VSM, FE-SEM/EDX, BJH/BET, and FTIR. The effects of several experimental factors on the uptake of MB using Fe3O4-GLP@CAB were examined through batch experiments. The highest MB dye removal efficiency of Fe3O4-GLP@CAB was obtained to be 95.2 % at pH 10.0. Adsorption equilibrium isotherm data at different temperatures showed an excellent agreement with the Langmuir model. The adsorption uptake of MB onto Fe3O4-GLP@CAB was determined as 136.7 mg/g at 298 K. The kinetic data were well-fitted by the pseudo-first-order model, indicating that physisorption mainly controlled it. Several thermodynamic variables derived from adsorption data, like as ΔGo, ΔSo, ΔHo, and Ea, accounted for a favourable, spontaneous, exothermic, and physisorption process. Without seeing a substantial decline in adsorptive performance, the Fe3O4-GLP@CAB was employed for five regeneration cycles. Because they can be readily separated from wastewater after treatment, the synthesized Fe3O4-GLP@CAB was thus regarded as a highly recyclable and effective adsorbent for MB dye.
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Nanopartículas , Psidium , Poluentes Químicos da Água , Adsorção , Pós , Azul de Metileno/química , Alginatos/química , Hidrogéis , Fenômenos Magnéticos , Folhas de Planta , Poluentes Químicos da Água/química , Cinética , Concentração de Íons de HidrogênioRESUMO
The ubiquitous and refractory benzophenone (BP)-type ultraviolet filters, which are also endocrine disruptors, were commonly detected in the aquatic matrix and could not be efficiently removed by conventional wastewater treatment processes, thus causing extensive concern. Herein, a novel ternary nanocomposite, P-g-CN/α-Bi2O3/WO3 (P-gBW), was successfully fabricated by mixing cocalcinated components and applied to the decomposition of BP-type ultraviolet filters. The dual-Z-scheme heterostructure of P-gBW enhances visible-light absorption, efficiently facilitates separation and mobility, and prolongs the lifetime of photoinduced charge carriers via double charge transfer mechanisms. The optimum 95 wt% P-gBW exhibited excellent photocatalytic activity, degrading 96% 4-hydroxy benzophenone (4HBP) within 150 min and 93% 2,2',4,4'-tetrahydroxybenzophenone (BP-2) within 100 min under visible-light illumination, respectively. The pseudo-first-order rate constant of 4HBP (1.15 h-1) was 6.8-, 3.1-, 3.3- and 2.2-fold higher than those of WO3, P-g-CN, α-Bi2O3, and P-g-CN/α-Bi2O3, respectively, while that of BP-2 (1.71 h-1) was 5.2-, 2.2-, 3.2- and 1.5-fold higher, respectively. The improved photocatalytic degradation was attributed to efficient photoinduced charge carrier separation and migration and prevented the recombination of electron holes, as verified by photoluminescence, transient photocurrent response, and electrochemical impedance spectroscopy. Trapping experiments, electron paramagnetic resonance, and band energy position indicated an efficient dual-Z-scheme heterostructure.