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Water and energy are closely linked and are crucial for national security and economic development. Most water providers prioritise the stability of water supply and aim to reduce energy consumption under the premise of a stable supply. The average energy required to supply water in Taiwan in one of the lowest worldwide. In the Kaohsiung area, the average energy used by a water purification plant to provide 1 m3 of water is 0.32 kWh/m3, lower than the world average of 0.37 kWh/m3. However, the most energy-consuming plant (Weng Park water purification plant) uses eight times as much energy as the least energy-consuming plant (Pingding water purification plant). Most studies focus on the energy required to provide 1 m3 of water. This study combined attributes of four plants, such as the amount of energy consumed, quantity of water supplied, purified, and collected, and weather data. These data were used to model energy baselines for water providers. Artificial intelligence was imported into Microsoft Azure machine learning to train the model, which was verified using another Kaohsiung plant and one overseas to establish an online energy baseline modelling system that can be applied in various water purification plants.
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In seeking sustainable environmental strategies, microbial biophotoelectrochemistry (BPEC) systems represent a significant advancement. In this review, we underscore the shift from conventional bioenergy systems to sophisticated BPEC applications, emphasizing their utility in leveraging solar energy for essential biochemical conversions. Recent progress in BPEC technology has facilitated improved photoelectron transfer and system stability, resulting in substantial advancements in carbon and nitrogen fixation, degradation of pollutants, and energy recovery from wastewater. Advances in system design and synthetic biology have expanded the potential of BPEC for environmental clean-up and sustainable energy generation. We also highlight the challenges of environmental BPEC systems, ranging from performance improvement to future applications.
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Photoelectrocatalysis (PEC) oxidation technology with the combination of electrocatalysis and photocatalysis is an ideal candidate for treatment of dyeing wastewater containing multifarious intractable organic compounds with high chroma. Constructing high-quality heterojunction photoelectrodes can effectively suppress the recombination of photo-generated carriers, thereby achieving efficient removal of pollution. Herein, a beaded Bi2MoO6@α-MnO2 core-shell architecture with tunable hetero-interface was prepared by simple hydrothermal-solvothermal process. The as-synthesized Bi2MoO6@α-MnO2 had larger electrochemically active surface area, smaller charge transfer resistance and negative flat band potential, and higher separation efficiency of e-/h+ pairs than pure α-MnO2 or Bi2MoO6. It is noteworthy that the as-synthesized Bi2MoO6@α-MnO2 showed Z-scheme heterostructure as demonstrated by the free radical quenching experiments. The optimized Bi2MoO6@α-MnO2-2.5 exhibited the highest degradation rate of 88.64% in 120 min for reactive brilliant blue (KN-R) and accelerated stability with long-term(â¼10000s) at the current density of 50 mA cm-2 in 1.0 mol L-1 H2SO4 solution. This study provides valuable insights into the straightforward preparation of heterogeneous electrodes, offering a promising approach for the treatment of wastewater in various industrial applications.
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Compostos de Manganês , Águas Residuárias , Águas Residuárias/química , Catálise , Compostos de Manganês/química , Óxidos/química , Bismuto/química , Poluentes Químicos da Água/química , Oxirredução , Técnicas Eletroquímicas , MolibdênioRESUMO
Agarose/micrometer titanium dioxide (TiO2) beads were essayed to test the photocatalytic capacity of two of the most widely prescribed drugs worldwide: paracetamol and ibuprofen. Although the initial tests demonstrated promising degradation rates for both drugs, the presence of turbidity, due to TiO2 leakage, during the photocatalytic essays induced to improve the stability of the photocatalytic composites. Among the different strategies adopted to strengthen such materials, crosslinking with citric acid and the use of alternative gelling agents: gellan, agargel™, and agar were chosen. Composites obtained by merging both strategies were characterized and employed to degrade both drugs under a simulated light that mimics the solar spectrum (indoor). Considering the superior degradation rates obtained when agar and agarose were used to shape the titanium oxide particles (up to 70-75% of drug destruction), such composites were subjected to a more realistic experiment (outdoor): solar illumination, tap water, and higher volumes, that should facilitate its ulterior scale up as a real wastewater depollution procedure. Degradation rates between 80 and 90% are attained under such conditions for both drugs.
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Acetaminofen , Hidrogéis , Ibuprofeno , Titânio , Águas Residuárias , Poluentes Químicos da Água , Titânio/química , Ibuprofeno/química , Águas Residuárias/química , Acetaminofen/química , Hidrogéis/química , Poluentes Químicos da Água/químicaRESUMO
In this research, a novel nano-biocomposite material, namely, tungsten trioxide-Butea monosperma leaf powder (WO3@BLP), is an effective and eco-friendly adsorbent used for the mitigation of congo red (CR) and crystal violet (CV) dyes from its aqueous phase. The as-prepared WO3@BLP was characterized using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), DLS analysis, and TGA. Many factors such as solution pH, WO3@BLP dose, temperature, contact time, and initial CR/CV dye concentrations were exploited to monitor the adsorption efficiency of WO3@BLP composites. The biosorption of both CR and CV dyes followed the Langmuir isotherm, with maximum adsorption capacities (qmax) reaching 84.91 mg g-1 for CR at pH 2.3 and 162.75 mg g-1 for CV at pH 8, fitting of kinetics data to the PSO model with closed values of qeexp (mg g-1) and qecal (mg g-1), i.e., 25.69 to 25.38 mg g-1 for CR dye and 29.06 to 29.08 mg g-1 for CV dye. The interaction mechanism behind the adsorption of CR and CV dyes onto the WO3@BLP bionanocomposite includes electrostatic interaction and surface complexation. The synthesized materials were tested for antifungal activity against three different Candida cells, i.e., C. albicans ATCC 90028, C. glabrata ATCC 90030, and C. tropicalis ATCC 750, by using broth dilution method on the minimum inhibiting concentration (MIC). Furthermore, the cytotoxicity of nano-formulated WO3@BLP was studied by in vitro hemolytic assay on a human host. Overall, this research presents a pioneering nano-biocomposite, WO3@BLP, as a sustainable adsorbent for CR and CV dye removal, adhering to Langmuir isotherm and pseudo-second-order kinetics. Its multifaceted approach includes elucidating interaction mechanisms, demonstrating antifungal activity, and assessing cytotoxicity, marking a significant advancement in environmental remediation.
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Folhas de Planta , Tungstênio , Purificação da Água , Purificação da Água/métodos , Tungstênio/química , Folhas de Planta/química , Adsorção , Poluentes Químicos da Água/química , Óxidos/química , Vermelho CongoRESUMO
Struvite crystallization, a promising technology for nutrient recovery from wastewater, is facing considerable challenges due to the presence of emerging contaminants such as microplastics (MPs) ubiquitously found in wastewater. Here, we investigate the roles of MPs and humic acid (HA) in struvite crystallization in batch and fluidized-bed reactors (FBRs) using synthetic and real wastewater with a Mg:N:P molar ratio of 1:3:(1-1.3) at an initial pH of 11. Batch reactor (BR) experiment results show that MPs expedited the nucleation and growth rates of struvite (e.g., the rate of crystal growth in the presence of 30 mg L-1 of polyethylene terephthalate (PET) was 1.43 times higher than that in the blank system), while HA hindered the formation of struvite. X-ray diffraction and the Rietveld refinement analysis revealed that the presence of MPs and HA can result in significant changes in phase compositions of the reclaimed precipitates, with over 80 % purity of struvite found in the precipitates from suspensions in the presence of 30 mg L-1 of MPs. Further characterizations demonstrated that MPs act as seeds of struvite nucleation, spurring the formation of well-defined struvite, while HA favors the formation of newberyite rather than struvite in both reactors. These findings highlight the need for a more comprehensive understanding of the interactions between emerging contaminants and struvite crystallization processes to optimize nutrient recovery strategies for mitigating their adverse impact on the quality and yield of struvite-based fertilizers. ENVIRONMENTAL IMPLICATION: The presence of microplastics in wastewater poses a significant challenge to struvite crystallization for nutrient recovery, as it accelerates nucleation and growth rates of struvite crystals. This can lead to changes in the phase compositions of the reclaimed precipitates, with implications for the quality and yield of struvite-based fertilizers. Additionally, the presence of humic acid hinders the formation of struvite, favoring the formation of other minerals like newberyite. Understanding the interactions between emerging contaminants and struvite crystallization processes is crucial for optimizing nutrient recovery strategies and mitigating the environmental impact of these contaminants on water quality and struvite-based fertilizers.
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The removal of dye molecules in alkaline environments is an issue that should receive increased attention. In this study, the interaction mechanism between polydopamine-modified multiwalled carbon nanotubes (P-MWCNTs) and multiwalled carbon nanotubes (MWCNTs) with the cationic dye methylene blue (MB) in alkaline environments was explained in depth by adsorption, spectroscopy, and density functional theory (DFT). The mechanism of action and dominant forces between the adsorbent and adsorbate were analyzed graphically by introducing energy decomposition analysis (EDA) and an independent gradient model (IGM) into the DFT calculations. In addition, the force distribution was investigated through an isosurface. Moreover, batch adsorption studies were conducted to evaluate the performance of MWCNTs and P-MWCNTs for MB removal in alkaline environments. The maximum MB adsorption capacities of the MWCNTs and P-MWCNTs in solution were 113.3 mgâ§g-1 and 230.4 mgâ§g-1, respectively, at pH 9. The IGM and EDA showed that the better adsorption capacity of the P-MWCNTs originated from the enhancement of the electrostatic effect by the proton dissociation of polydopamine. Moreover, the adsorption of MB by MWCNTs and P-MWCNTs in alkaline environments was governed by dispersion and electrostatic effects, respectively. Through this study, it is hoped that progress will be made in the use of DFT to explore the mechanism of adsorbent-adsorbate interactions.
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Ozone generation is a water disinfection method, superior to chlorine in terms of fewer byproducts and no residual taste. However, its high production cost limits its widespread adoption. This paper designs an ozone generation sinusoidal power supply for water treatment. Ozone generation requires a high-frequency and high-voltage power supply to produce ozone from oxygen molecules. The study evaluates two power supply topologies, one with a parallel LC filter and the other with an LCL filter, assessing their feasibility, effectiveness, and reliability. Theoretically, the LCL filter achieves higher gains than the parallel LC filter. The larger inductance in the parallel LC filter reduces gain, while the larger inductance in the LCL filter increases gain. Simulation and practical results validate these findings, achieving gains of 40 for the parallel LC filter and 150 for the LCL filter.
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Graphene oxide (GO) membranes have emerged as promising candidates for water purification applications, owing to their unique physicochemical attributes. Nevertheless, the trade-off between permeability and selectivity, coupled with their vulnerability to membrane fouling, poses significant challenges to their widespread industrial deployment. In this study, we introduce an innovative in-situ growth and layer-by-layer assembly technique for fabricating multilayer GO membranes reinforced with bismuth oxybromide (BiOBr) on commonly employed Nylon substrates. This method allows for the creation of two-dimensional lamellar membranes capable of photocatalytic self-cleaning and tunable nanochannel dimensions. The synthesized GO/BiOBr composite membranes exhibit remarkable water permeance rates (approximately 493.9 LMH/bar) and high molecular rejection efficiency (>99 % for Victoria Blue B and Congo Red dyes). Notably, these membranes showcase an enhanced photocatalytic self-cleaning performance upon exposure to visible light. Our work provides a viable route for the fabrication of functionalized GO-based nanofiltration membranes with BiOBr inclusions, offering a synergistic combination of high water permeability, modifiable nanochannels, and effective self-cleaning capabilities through photocatalysis.
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The photoelectrocatalytic advanced oxidation process (PEAOP) necessitates high-performing and stable photoanodes for the effective oxidation of complex pollutants in industrial wastewater. This study presents the construction of 2D WO3/MXene heteronanostructures for the development of efficient and stable photoanode. The WO3/MXene heterostructure features well-ordered WO3 photoactive sites anchored on micron-sized MXene sheets, providing an increased visible light active catalytic surface area and enhanced electrocatalytic activities for pollutant oxidation. Phenol, a highly toxic compound, was completely oxidized at an applied potential of 0.8 V vs. RHE under visible light irradiation. Systematic optimization of operational conditions for the photoelectrocatalytic oxidation of phenol was conducted. The phenol oxidation mechanism was elucidated via high-performance liquid chromatography (HPLC) analysis and the identification of intermediate compounds. Additionally, a mixed model of phenol and arsenic (III) in polluted water demonstrated the capability of WO3/MXene photoanode for the simultaneous oxidation of both organic and inorganic pollutants, achieving complete conversion of phenol and As(III) to non-toxic As(V). The WO3/MXene photoanode facilitated water oxidation, generating a substantial amount of O2â¢- and â¢OH oxidative species, which are crucial for the concurrent oxidation of phenol and arsenic. Recyclability tests demonstrated a 99% retention of performance, confirming the WO3/MXene photoanode's suitability for long-term operation in PEAOPs. The findings suggest that integrating WO3/MXene photoanodes into water purification systems can enhance economic feasibility, reduce energy consumption, and improve efficiency. This PEAOP offers a viable solution to the critical issue of heavy metal and organic chemical pollution in various water bodies, given its scalability and ability to preserve ecosystems while conserving clean water resources.
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In this study, the removal effect of a new MOF-on MOF adsorbent based on Cu-Co bimetallic organic frameworks on tetracycline antibiotics (TCs) in water system was studied. The adsorbent (Cu-MOF@Co-MOF) were synthesized by solvothermal and self-assembly method at different concentrations of Co2+/Cu2+. The characterization results of SEM, XRD, XPS, FTIR and BET indicated that the MOF-on MOF structure of Cu-MOF@Co-MOF exhibited the best recombination and physicochemical properties when the molar ratio of Co2+: Cu2+ is 5:1. In addition, the Cu-MOF@Co-MOF have a high specific surface area and bimetallic clusters, which can achieve multi-target synergistic adsorption of TCs. Based on above advantages, Cu-MOF@Co-MOF provided a strong affinity and could efficiently adsorb more than 80% of pollutants in just 5 to 15 min using only 10 mg of the adsorbent. The adsorption capacity of tetracycline and doxycycline was 434.78 and 476.19 mg/g, respectively, showing satisfactory adsorption performance. The fitting results of the experimental data were more consistent with the Langmuir isotherm model and pseudo-second-order kinetic model, indicating that the adsorption process of TC and DOX occurred at the homogeneous adsorption site and was mainly controlled by chemisorption. Thermodynamic experiments showed that Cu-MOF@Co-MOF was thermodynamically advantageous for the removal of TCs, and the whole process was spontaneous. The excellent adsorption capacity and rapid adsorption kinetics indicate the prepared MOF-on MOF adsorbent can adsorb TCs economically and quickly, and have satisfactory application prospects for removing TCs in practical environments. The results of the study pave a new way for preparing novel MOFs-based water treatment materials with great potential for efficient removal.
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Antibacterianos , Cobre , Estruturas Metalorgânicas , Tetraciclina , Poluentes Químicos da Água , Purificação da Água , Adsorção , Cobre/química , Estruturas Metalorgânicas/química , Antibacterianos/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Tetraciclina/química , Tetraciclina/isolamento & purificação , Purificação da Água/métodos , Cobalto/química , CinéticaRESUMO
Given its profound disservice, a bacteria-microalgae-fungi combined system was designed to treat kitchen waste. Firstly, a new type of microbial agent homemade compound microorganisms (HCM) (composed of Serratia marcescens, Bacillus subtilis and other 11 strains) with relatively high bio-security were developed for pretreating kitchen waste, and HCM efficiently degraded 85.2 % cellulose, 94.3 % starch, and 59.0 % oil. HCM also accomplished brilliantly the initial nutrients purification and liquefaction conversion of kitchen waste. Under mono-culture mode (fungi and microalgae were inoculated separately in the pre - and post-stages) and co-culture mode (fungi and microalgae were inoculated simultaneously in the early stage), microalgae-fungi consortia were then applied for further water purification and resource utilization of kitchen waste liquefied liquid (KWLL) produced in the pretreatment stage. Two kinds of microalgae-fungi consortia (Chlorella sp. HQ and Chlorella sp. MHQ2 form consortia with pellet-forming fungi Aspergillus niger HW8-1, respectively) removed 79.5-83.0 % chemical oxygen demand (COD), 44.0-56.5 % total nitrogen (TN), 90.3-96.4 % total phosphorus (TP), and 64.9-71.0 % NH4+-N of KWLL. What's more, the microalgae-fungi consortia constructed in this study accumulated abundant high-value substances at the same time of efficiently purifying KWLL. Finally, in the biomass harvesting stage, pellet-forming fungi efficiently harvested 81.9-82.1 % of microalgal biomass in a low-cost manner through exopolysaccharides adhesion, surface proteins interaction and charge neutralization. Compared with conventional microalgae-bacteria symbiosis system, the constructed bacteria-microalgae-fungi new-type combined system achieves the triple purpose of efficient purification, resource utilization, and biomass recovery on raw kitchen waste through the trilogy strategy, providing momentous technical references and more treatment systems selection for future kitchen waste treatment.
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Biomassa , Microalgas , Eliminação de Resíduos Líquidos/métodos , Bactérias , Fungos , Biodegradação Ambiental , Purificação da Água/métodosRESUMO
A lot of research has been focused on increasing the specific surface area of adsorbents over a long period of time to remove heavy metal ions from wastewater using the adsorbent. However, porous adsorbents with high specific surface area have demonstrated drawbacks in water purification processes, such as high pressure drop and limitations in the adsorption capacity of heavy metal ions. In recent years, a mechanism-based convergence method involving adsorption/chemical precipitation has emerged as a promising strategy to surmount the constraints associated with porous adsorbents. The mechanism involves amine groups on chelating fibers dissociating OH- ions from water molecules, thereby raising the pH near the fibers. This elevated pH promotes the crystallization of heavy metal ions on the fiber surfaces. The removal of heavy metal ions proceeds through a sequence of adsorption and chemical precipitation processes. An adsorbent based on chelating fibers, integrating adsorption technology with chemical precipitation, demonstrates superior performance in removing significant quantities of heavy metal ions (ca. 1000-2000 mg/g for Cd2+, Cu2+ and Pb2+) when compared to developed porous adsorbents (ca. 50-760 mg/g for same ions). This review paper introduces advanced polymer fibers endowed with the capability to integrate hybrid technology, delves into the mechanism of hybrid technology, and examines its application in process technology for the effective removal of heavy metal ions. The versatility of these advanced fibers extends far beyond the removal of heavy metal ions in water treatment, making them poised to garner significant attention from researchers across diverse fields due to their broad range of potential applications. After further processes involving the removal of templates from chelating polymeric fibers used as supports and the reduction of precipitated heavy metal oxide crystals, the resulting heavy metal crystals can exhibit thin walls and well-interconnected porous structures, suitable for catalytic applications.
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Precipitação Química , Metais Pesados , Polímeros , Poluentes Químicos da Água , Purificação da Água , Metais Pesados/química , Adsorção , Purificação da Água/métodos , Poluentes Químicos da Água/química , Polímeros/química , Águas Residuárias/química , Porosidade , Íons/químicaRESUMO
Improving water quality to provide freshwater is an urgent requirement for regional and even global social development. More accurate simulation of non-point sources pollution, monitored mainly by total nitrogen (TN) and total phosphorus (TP), has always been a challenge for InVEST water purification model, particularly in agricultural areas. This can be attributed to the fact that there is no reference data for TN and TP to rectify the outcomes modelled by this model. This paper provided these data to rectify simulation results of TN and TP to ensure their accuracy. The Huai River watershed (HRW) is an important grain production area with slow economic development, and non-point source pollution has exceeded point-source pollution. There is an urgent need for water management authorities to obtain complete spatio-temporal data on TN and TP loads and their exports to improve water quality. The reference data onloads and exports of TN and TP were estimated for the entire watershed and its sub-watersheds through an investigation-evaluation technique during 1980-2018. TN and TP loads generated from the agricultural sector were the major pollution sources in the HRW and had similar time trends during the same period. The spatial distribution of TN and TP exports was modelled byusingthe InVEST water purification model, and it was found that the temporal trends for the final exports of TN and TP into river systems were similar to those for TN and TP loads in the HRW for 1980-2018. Key driving factors were detected using the Geo-detector method to quantify the contribution rates of factors to the spatiotemporal exports of TN and TP. Our results showed that individual factors, such as precipitation and land use/cover, were the most important factors driving spatio-temporal variations in TN and TP exports in the HRW from 1980 to 2018. Meanwhile, the contribution rates of interactions between land use/cover and other factors were consistently highest in this watershed during the same period. In this study, we estimated the loads and exports of TN and TP, and modelled their spatial patterns in this watershed from 1980 to 2018, providing important information on TN and TP for water-related management authorities. We also provide a method for other river systems to calibrate the parameters in the biophysical table of InVEST water purification model based on final exports of TN and TP.
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Nitrogênio , Fósforo , Rios , Fósforo/análise , Nitrogênio/análise , Rios/química , China , Purificação da Água/métodos , Monitoramento Ambiental/métodos , Modelos Teóricos , Qualidade da Água , Poluentes Químicos da Água/análiseRESUMO
Water pollution is one of serious environmental issues due to the rapid development of industrial and agricultural sectors, and clean water resources have been receiving increasing attention. Recently, more and more studies have witnessed significant development of catalysts (metal oxides, metal sulfides, metal-organic frameworks, zero-valent metal, etc.) for wastewater treatment and water purification. Sustainable and clean catalysts immobilized into chitosan-based materials (Cat@CSbMs) are considered one of the most appealing subclasses of functional materials due to their high catalytic activity, high adsorption capacities, non-toxicity and relative stability. This review provides a summary of various upgrading renewable Cat@CSbMs (such as cocatalyst, photocatalyst, and Fenton-like reagent, etc.). As for engineering applications, further researches of Cat@CSbMs should focus on treating complex wastewater containing both heavy metals and organic pollutants, as well as developing continuous flow treatment methods for industrial wastewater using Cat@CSbMs. In conclusion, this review abridges the gap between different approaches for upgrading renewable and clean Cat@CSbMs and their future applications. This will contribute to the development of cleaner and sustainable Cat@CSbMs for wastewater treatment and water purification.
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Quitosana , Águas Residuárias , Poluentes Químicos da Água , Purificação da Água , Quitosana/química , Purificação da Água/métodos , Catálise , Águas Residuárias/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Metais Pesados/química , Metais Pesados/isolamento & purificaçãoRESUMO
Creating new adsorbents is crucial for removing contaminants from water due to increased industrialization, which has worsened water pollution in recent years. In this study, a magnetic biocomposite, Zirconium (Zr)-doped chitosan (CS)-coated iron oxide nanoparticles (Fe3O4-NPs)-peanut husk (PH)-based activated carbon (AC) (Zr-CS/Fe3O4-NPs@PH-AC), was synthesized for efficient removal of alizarin red (AR) and congo red (CR) dyes, alongside antibacterial applications. Characterization via scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) analysis revealed micropores and mesopores development due to chemical activation of PH biomaterial and Fe3O4-NPs addition. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) identified functional groups and structural properties. Vibrating sample magnetometry (VSM) analyzed magnetic properties. Optimal conditions for AR/CR removal were determined, including Zr-CS/Fe3O4-NPs@PH-AC dose, dye dose, contact time, and temperature, achieving maximum removal percentages. Experimentally determined maximum adsorption capacities for AR and CR were 374.3 and 154.1 mg·g-1, respectively. Cytotoxicity studies affirmed the eco-friendly and non-toxic nature of the adsorbent by exhibiting the reduction in the cell viability from 100 % to 88.68 % from the 0 to 200 µg·L-1 respectively. Additionally, the biocomposite exhibited significant antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) due to magnetic NPs. The material in this study shows extreme compatibility for numerous applications.
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Antibacterianos , Carvão Vegetal , Quitosana , Vermelho Congo , Águas Residuárias , Poluentes Químicos da Água , Zircônio , Quitosana/química , Zircônio/química , Vermelho Congo/química , Antibacterianos/farmacologia , Antibacterianos/química , Adsorção , Águas Residuárias/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Carvão Vegetal/química , Purificação da Água/métodos , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , AntraquinonasRESUMO
Membrane materials that resist nonspecific or specific adsorption are urgently required in widespread practical applications, such as water purification, food processing, and life sciences. In water purification, inevitable membrane fouling not only limits membrane separation performance, leading to a decline in both permeance and selectivity, but also remarkably increases operation requirements, and augments extra maintenance costs and higher energy consumption. In this work, we report a freestanding interfacial polymerization (IP) fabrication strategy for in situ creation of asymmetric block copolymer (BCP) nanofilms with antifouling properties, greatly outperforming the conventional surface post-modification approaches. The resultant free-standing asymmetric BCP nanofilms with highly-dense, highly-hydrophilic polyethylene glycol (PEG) brushes on one side, can be readily formed via a typical IP process of a well-defined double-hydrophilic BCP composed of a highly-efficient antifouling PEG block and a membrane-forming multiamine block. The asymmetric BCP nanofilms have been applied for efficient and sustainable natural water purification, demonstrating extraordinary antifouling capabilities accompanied with superior separation performance far beyond commercial polyamide nanofiltration membranes. The antifouling behaviors of asymmetric BCP nanofilms derived from the combined effect of the hydration layer, electrostatic repulsion and steric hindrance were further elucidated by water flux and fouling resistance in combination with all-atom molecular dynamics (MD) simulation. This work opens up a new avenue for the large-scale and low-cost creation of broad-spectrum, asymmetric membrane materials with diverse functional "defect-free" surfaces in real-world applications.
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Significant progress has been made previously in the research and development of graphene oxide (GO) membranes for water purification, but their biofouling behavior remains poorly understood. In this study, we investigated the biofilm formation and biofouling of GO membranes with different surface microstructures in the context of filtering natural surface water and for an extended operation period (110 days). The results showed that the relatively hydrophilic and smooth Fe(OH)3/GO membrane shaped a thin and spatially heterogeneous biofilm with high stable flux. However, the ability to simultaneously mitigate biofilm formation and reduce biofouling was not observed in the weakly hydrophilic and wrinkled Fe/GO and H-Fe(OH)3/GO membranes. Microbial analyses revealed that the hydrophilicity and roughness distinguished the bacterial communities and metabolic functions. The organic matter-degrading and predatory bacteria were more adapted to hydrophilic and smooth GO surfaces. These functional taxa were involved in the degradation of extracellular polymeric substances (EPS), and improved biofilm heterogeneity. In contrast, the weakly hydrophilic and wrinkled GO surfaces had reduced biodiversity, while unexpectedly boosting the proliferation of EPS-secreting bacteria, resulting in increased biofilm formation and aggravated biofouling. Moreover, all GO membranes achieved sustainable water purification during the entire operating period.
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Biofilmes , Incrustação Biológica , Grafite , Purificação da Água , Grafite/química , Membranas Artificiais , Óxidos/químicaRESUMO
In recent years, MXene has become one of the most intriguing two-dimensional layered (2Dl) materials extensively explored for various applications. In this study, a Ti3C2 MXene/rGo-Cu2O Nanocomposite (TGCNCs) was developed to eliminate Safranin-O effectively (SO) and Acid Fuchsin (AF) as cationic dyes from the aquatic environment. Multistep was involved in the preparation of the adsorbent system, including the Preparation of Ti3C2, after that, GO synthesis by the Humer method, followed by rGO production, then added CuSO4 to obtain a final Nanocomposite (NCs) called "TGCNCs". The structure of TGCNCs can be varied in several ways, including FTIR, SEM, TGA, Zeta, EDX, XRD, and BET, to affirm the efficacious preparation of TGCNCs. A novel adsorbent system was developed to remove SO and AF, both cationic dyes. Various adsorption conditions have been optimized through batch adsorption tests, including the pH of the solution (4-12), the effect of dosage (0.003-0.03 g), the impact of the contact time (5-30 min), and the effect of beginning dye concentration (25-250 mg/L). Accordingly, the TGCNCs exhibited excellent fitting for Freundlich isotherm mode, resulting in maximum AF and SO adsorption capacities of 909.09 and 769.23 mg g-1. This research on adsorption kinetics suggests that a pseudo-second-order (PSO) model would fit well with the experimental data (RSO2 = 0.998 and RAF2 = 0.990). It is evident from the thermodynamic parameters that adsorption is an endothermic process that is spontaneous and favorable. During the adsorption of SO and AF onto NCs, it is hypothesized that these molecules interact intramolecularly through stacking interactions, H-bond interactions, electrostatic interactions, and entrapment within the polymeric Poros structure nanocomposite. Regeneration studies lasting up to five cycles were the most effective for both organic dyes under study.
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Cobre , Nanocompostos , Fenazinas , Termodinâmica , Titânio , Poluentes Químicos da Água , Nanocompostos/química , Fenazinas/química , Cinética , Adsorção , Titânio/química , Poluentes Químicos da Água/química , Cobre/química , Corantes/química , Corantes de Rosanilina/química , Grafite/química , BenzenossulfonatosRESUMO
The demands of human life and industrial activities result in a significant influx of toxic contaminants into aquatic ecosystems. In particular, organic pollutants such as antibiotics and dye molecules, bacteria, and heavy metal ions are represented, posing a severe risk to the health and continued existence of living organisms. The method of removing pollutants from water bodies by utilizing the principle of the piezoelectric effect in combination with chemical catalytic processes is superior to other wastewater purification technologies because it can collect water energy, mechanical energy, etc. to achieve cleanliness and high removal efficiency. Herein, we briefly introduced the piezoelectric mechanisms and then reviewed the latest advances in the design and synthesis of piezoelectric materials, followed by a summary of applications based on the principle of piezoelectric effect to degrade pollutants in water for wastewater purification. Moreover, water purification technologies incorporating the piezoelectric effect, including piezoelectric effect-assisted membrane filtration, activation of persulfate, and battery electrocatalysis are elaborated. Finally, future challenges and research directions for the piezoelectric effect are proposed.