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1.
Water Sci Technol ; 89(9): 2290-2310, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38747950

RESUMEN

In the face of growing global freshwater scarcity, the imperative to recycle and reuse water becomes increasingly apparent across industrial, agricultural, and domestic sectors. Eliminating a range of organic pollutants in wastewater, from pesticides to industrial byproducts, presents a formidable challenge. Among the potential solutions, membrane technologies emerge as promising contenders for treating diverse organic contaminants from industrial, agricultural, and household origins. This paper explores cutting-edge membrane-based approaches, including reverse osmosis, nanofiltration, ultrafiltration, microfiltration, gas separation membranes, and pervaporation. Each technology's efficacy in removing distinct organic pollutants while producing purified water is scrutinized. This review delves into membrane fouling, discussing its influencing factors and preventative strategies. It sheds light on the merits, limitations, and prospects of these various membrane techniques, contributing to the advancement of wastewater treatment. It advocates for future research in membrane technology with a focus on fouling control and the development of energy-efficient devices. Interdisciplinary collaboration among researchers, engineers, policymakers, and industry players is vital for shaping water purification innovation. Ongoing research and collaboration position us to fulfill the promise of accessible, clean water for all.


Asunto(s)
Membranas Artificiales , Contaminantes Químicos del Agua , Purificación del Agua , Purificación del Agua/métodos , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos , Filtración/métodos , Filtración/instrumentación , Ultrafiltración/métodos , Compuestos Orgánicos/aislamiento & purificación
2.
Water Sci Technol ; 89(9): 2558-2576, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38747967

RESUMEN

In this study, membranes blended with polysulfone (PSU) and polyetherimide (PEI) polymers in different ratios were fabricated. Their potential to remove pollutants from rivers, which are a potential drinking water source, was investigated. Scanning electron microscopy analysis revealed that the PSU membranes had a dense and homogeneous layer, whereas the addition of PEI formed a spongy substrate. The water content of the fabricated membranes varied between 5.37 and 22.42%, porosities 28.73-89.36%, contact angles 69.18-85.81%, and average pure water fluxes 257.25-375.32 L/m2 h. The blended membranes removed turbidity, chloride, alkalinity, conductivity, sulfate, iron, manganese, and total organic carbon up to 98.32, 92.28, 96.87, 90.67, 99.58, 94.63, 97.48, and 79.11%, respectively. These results show that when PEI was added to the PSU polymer, the filtration efficiency increased owing to an increase in the hydrophilicity of the membranes. Blending these two polymers enabled the optimization of membrane properties such as permeability, selectivity, and mechanical strength. In addition, membrane fabrication processes are simple and incur low costs.


Asunto(s)
Filtración , Membranas Artificiales , Polímeros , Sulfonas , Polímeros/química , Sulfonas/química , Filtración/métodos , Purificación del Agua/métodos , Contaminantes Químicos del Agua/química , Microscopía Electrónica de Rastreo
3.
Sci Rep ; 14(1): 10872, 2024 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-38740837

RESUMEN

Urine is a rich source of nucleic acid biomarkers including cell-free DNA (cfDNA) and RNA for monitoring the health of kidney allografts. In this study, we aimed to evaluate whether urine filtration can serve as an alternative to the commonly used method of centrifugation to collect urinary fluid and cell pellets for isolating cfDNA and cellular messenger RNA (mRNA). We collected urine specimens from kidney allograft recipients and obtained the urine supernatant and cell pellet from each specimen using both filtration and centrifugation for paired analyses. We performed DNA sequencing to characterize the origin and properties of cfDNA, as well as quantitative PCR of mRNAs extracted from cell fractions. Our results showed that the biophysical properties of cfDNA, the microbial DNA content, and the tissues of origin of cfDNA were comparable between samples processed using filtration and centrifugation method. Similarly, mRNA quality and quantity obtained using both methods met our criteria for downstream application and the Ct values for each mRNA were comparable between the two techniques.The Ct values demonstrated a high degree of correlation. These findings suggest that urine filtration is a viable alternative to urine centrifugation for isolation of nucleic acid biomarkers from urine specimens.


Asunto(s)
Biomarcadores , Ácidos Nucleicos Libres de Células , Centrifugación , Filtración , Trasplante de Riñón , Humanos , Centrifugación/métodos , Biomarcadores/orina , Filtración/métodos , Ácidos Nucleicos Libres de Células/orina , Ácidos Nucleicos Libres de Células/aislamiento & purificación , Ácidos Nucleicos Libres de Células/análisis , ARN Mensajero/genética , ARN Mensajero/orina , Masculino , Femenino , Persona de Mediana Edad , Adulto , Orina/química
4.
PLoS One ; 19(5): e0302487, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38713701

RESUMEN

This study describes the operation of two independent parallel laboratory-scale biotrickling filters (BTFs) to degrade different types of binary volatile organic compound (VOC) mixtures. Comparison experiments were conducted to evaluate the effects of two typical VOCs, i.e., ethyl acetate (a hydrophilic VOC) and n-hexane (a hydrophobic VOC) on the removal performance of toluene (a moderately hydrophobic VOC) in BTFs ''A" and ''B", respectively. Experiments were carried out by stabilizing the toluene concentration at 1.64 g m-3 and varying the concentrations of gas-phase ethyl acetate (0.85-2.8 g m-3) and n-hexane (0.85-2.8 g m-3) at an empty bed residence time (EBRT) of 30 s. In the presence of ethyl acetate (850 ± 55 mg m-3), toluene exhibited the highest removal efficiency (95.4 ± 2.2%) in BTF "A". However, the removal rate of toluene varied from 48.1 ± 6.9% to 70.1 ± 6.8% when 850 ± 123 mg m-3 to 2800 ± 136 mg m-3 of n-hexane was introduced into BTF "B". The high-throughput sequencing data revealed that the genera Pseudomonas and Comamonadaceae_unclassified are the core microorganisms responsible for the degradation of toluene. The intensity of the inhibitory or synergistic effects on toluene removal was influenced by the type and concentration of the introduced VOC, as well as the number and activity of the genera Pseudomonas and Comamonadaceae_unclassified. It provides insights into the interaction between binary VOCs during biofiltration from a microscopic perspective.


Asunto(s)
Acetatos , Biodegradación Ambiental , Filtración , Hexanos , Tolueno , Compuestos Orgánicos Volátiles , Tolueno/metabolismo , Hexanos/química , Acetatos/metabolismo , Filtración/métodos , Compuestos Orgánicos Volátiles/metabolismo , Microbiota
5.
Anal Chim Acta ; 1307: 342624, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38719414

RESUMEN

BACKGROUND: Pesticides are used in agricultural production for prevent and control crop diseases and pests, but it is easy to cause excessive pesticides residues in agricultural products, polluting the environment and endangering human health. Due to their unmatched and sustainable capabilities, nanoextraction procedures are becoming every day more important in Analytical Chemistry. In particular, nanoconfined liquid phase extraction has shown extraction capabilities toward polar, medium polar, and/or nonpolar substances, which can be easily modulated depending on the nanoconfined solvent used. Furthermore, this "green" technique showed excellent characteristics in terms of recoveries, extraction time (≤1 min), reliability, and versatility. (97) RESULTS: In this work, the advantages of this technique have been coupled with those of filtration membrane extraction, making use of carbon nanofibers (CnFs) growth on carbon microspheres (CµS). This substrate has been deposited on a filter, which combined with gas chromatographic mass spectrometry (GC-MS) analysis successfully employed for the nanoextraction of 30 pesticides (18 organochlorine and 12 pyrethroids) in tea samples. Under the optimized extraction conditions, the linear range with standard solutions was from 1 to 1000 ng mL-1 (R2 ≥ 0.99), the limit of detections in tea samples were in the range 0.56-17.98 µg kg-1. The accuracy of the developed method was evaluated by measuring the extraction recovery of the spiked tea samples, and recoveries between 74.41 % and 115.46 %. (119) SIGNIFICANCE: Considering the versatility of nanoconfined liquid phase extraction and the functionality of the filtration membrane extraction procedure, this new extraction method can be considered a powerful candidate for automatized high-throughput analyses of real samples. (34).


Asunto(s)
Filtración , Hidrocarburos Clorados , Extracción Líquido-Líquido , Plaguicidas , Piretrinas , , Té/química , Piretrinas/análisis , Piretrinas/aislamiento & purificación , Hidrocarburos Clorados/análisis , Hidrocarburos Clorados/aislamiento & purificación , Extracción Líquido-Líquido/métodos , Filtración/métodos , Plaguicidas/análisis , Plaguicidas/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas/métodos , Membranas Artificiales
6.
Biotechnol J ; 19(5): e2400154, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38719568

RESUMEN

Maximizing product yield in biopharmaceutical manufacturing processes is a critical factor in determining the overall cost of goods, especially given the high value of these biological products. However, there has been relatively limited research on the quantitative analysis of protein losses due to adsorption and fouling during the different membrane filtration processes employed in typical downstream operations. This study aims to provide a comprehensive analysis of protein loss in the range of membrane systems used in downstream processing including clarification, virus removal filtration, ultrafiltration/diafiltration for formulation, and final sterile filtration, all using commercially available membranes with three model proteins (bovine serum albumin, human serum albumin, and immunoglobulin G). The correlation between protein loss and various parameters (i.e., protein type, protein concentration, throughput, membrane morphology, and protein removal mechanism) was also investigated. This study provides important insights into the nature of protein loss during membrane processes as well as a methodology for quantifying protein yield loss in bioprocesses.


Asunto(s)
Membranas Artificiales , Ultrafiltración , Humanos , Ultrafiltración/métodos , Filtración/métodos , Animales , Productos Biológicos/química , Albúmina Sérica Bovina/química , Inmunoglobulina G/química , Adsorción , Bovinos , Albúmina Sérica Humana/química
7.
Analyst ; 149(10): 2978-2987, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38602145

RESUMEN

Cultivation-independent molecular biological methods are essential to rapidly quantify pathogens like Legionella pneumophila (L. pneumophila) which is important to control aerosol-generating engineered water systems. A standard addition method was established to quantify L. pneumophila in the very complex matrix of process water and air of exhaust air purification systems in animal husbandry. Therefore, cryopreserved standards of viable L. pneumophila were spiked in air and water samples to calibrate the total bioanalytical process which includes cell lysis, DNA extraction, and qPCR. A standard addition algorithm was employed for qPCR to determine the initial concentration of L. pneumophila. In mineral water, the recovery rate of this approach (73%-134% within the concentration range of 100-5000 Legionella per mL) was in good agreement with numbers obtained from conventional genomic unit (GU) calibration with DNA standards. In air samples of biotrickling filters, in contrast, the conventional DNA standard approach resulted in a significant overestimation of up to 729%, whereas our standard addition gave a more realistic recovery of 131%. With this proof-of-principle study, we were able to show that the molecular biology-based standard addition approach is a suitable method to determine realistic concentrations of L. pneumophila in air and process water samples of biotrickling filter systems. Moreover, this quantification strategy is generally a promising method to quantify pathogens in challenging samples containing a complex microbiota and the classical GU approach used for qPCR leads to unreliable results.


Asunto(s)
Legionella pneumophila , Reacción en Cadena en Tiempo Real de la Polimerasa , Legionella pneumophila/aislamiento & purificación , Legionella pneumophila/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Filtración/métodos , Filtración/instrumentación , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , ADN Bacteriano/análisis , Microbiología del Agua , Microbiología del Aire
8.
Chemosphere ; 357: 141833, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38579944

RESUMEN

Experimental water research lacks clear methodology to estimate experimental error. Especially when natural waters are involved, the characterization tools bear method-specific artifacts while the varying environmental conditions prevent regular repeats. This tutorial review identifies common mistakes, and proposes a practical procedure to determine experimental errors at the example of membrane filtration. Statistical analysis is often applied to an insufficient number of repeated measurements, while not all error sources and contributions are considered. This results in an underestimation of the experimental error. Variations in relevant experimental parameters need to be investigated systematically, and the related errors are quantified as a half of the variation between the max and min values when standard deviation is not applicable. Error of calculated parameters (e.g. flux, pollutant removal and mass loss) is estimated by applying error propagation, where weighing contributions of the experimental parameters are considered. Appropriate judgment and five-time repetition of a selected experiment under identical conditions are proposed to validate the propagated experimental error. For validation, the five repeated data points should lie within the estimated error range of the error bar. The proposed error evaluation procedure is adaptable in experimental water research and intended for researchers to identify the contributing factors of an experimental error and carry out appropriate error quantification and validation. The most important aim is to raise awareness of the necessity to question error methodology and reproducibility of experimental data, to produce and publish high quality research.


Asunto(s)
Filtración , Membranas Artificiales , Filtración/métodos , Purificación del Agua/métodos , Agua/química , Reproducibilidad de los Resultados , Proyectos de Investigación , Error Científico Experimental/estadística & datos numéricos
9.
Chemosphere ; 357: 141982, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38608778

RESUMEN

Powdered activated carbon (PAC) has been extensively used as an effective adsorbent. Despite its excellent adsorption ability, PAC has drawbacks, including difficulty in filtration and reactivation after use, limitations of mass transfer in deeper areas because of its aggregated powder form, and limited applicability in high-flow systems. To overcome these limitations, we used a three-dimensional (3D) printing system to fabricate PAC into a 3D structure. Spectral and microscopic analyses indicated that PAC was embedded into 3D monolith and exhibited high porosity suitable for facile mass transfer. The designed 3D PAC filter effectively removed 200 ppm-methylene blue (MB) within 8 h and showed an adsorption efficiency of 93.4 ± 0.9%. The adsorption of MB onto the 3D PAC filter was described by the pseudo-first-order kinetic and Freundlich isotherm models. The negatively charged 3D PAC filter might attract the positively charged MB, thus favoring the physical adsorption of MB onto the 3D PAC filter. The adsorption performance of the 3D PAC filter was tested at various pH levels of 4-10 and against MB spiked in seawaters and freshwaters to evaluate its feasibility for use in real environments. Finally, the reproducibility and reusability of the 3D PAC filter were demonstrated through repeated adsorption and desorption processes against MB.


Asunto(s)
Carbón Orgánico , Colorantes , Azul de Metileno , Impresión Tridimensional , Contaminantes Químicos del Agua , Purificación del Agua , Carbón Orgánico/química , Adsorción , Colorantes/química , Contaminantes Químicos del Agua/química , Azul de Metileno/química , Purificación del Agua/métodos , Polvos , Cinética , Cationes/química , Filtración/métodos , Porosidad , Carbono/química , Concentración de Iones de Hidrógeno
10.
Water Sci Technol ; 89(8): 2020-2034, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38678406

RESUMEN

Nanofiltration (NF) membrane technology has been widely used in the removal of salts and trace organic pollutants, such as pharmaceuticals and personal care products (PPCPs), due to its superiority. A positive-charged composite NF membrane with an active skin layer was prepared by polyethyleneimine (PEI), trimethyl benzene chloride, and quaternate chitosan (HTCC) through second interfacial polymerization on the polyethersulfone ultrafiltration membrane. The physicochemical properties of the nanocomposite membrane were investigated using surface morphology, hydrophilicity, surface charge, and molecular weight cut-off (MWCO). The influence of the concentration and reaction time of PEI and HTCC was documented. The optimized membrane had a MWCO of about 481 Da and possessed a pure water permeability of 25.37 L·m-2·h-1·MPa-1. The results also exhibited salt rejection ability as MgCl2 > CaCl2 > MgSO4 > Na2SO4 > NaCl > KCl, showing a positive charge on the fabricated membrane. In addition, the membrane had higher rejection to atenolol, carbamazepine, amlodipine, and ibuprofen at 89.46, 86.02, 90.12, and 77.21%, respectively. Moreover, the anti-fouling performance and stability of the NF membrane were also improved.


Asunto(s)
Quitosano , Membranas Artificiales , Contaminantes Químicos del Agua , Quitosano/química , Contaminantes Químicos del Agua/química , Preparaciones Farmacéuticas/química , Purificación del Agua/métodos , Polimerizacion , Sales (Química)/química , Ultrafiltración/métodos , Filtración/métodos
11.
Chemosphere ; 356: 141960, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38604517

RESUMEN

Pesticides are used in agriculture to protect crops from pathogens, insects, fungi and weeds, but the release of pesticides into surface/groundwater by agriculture runoff and rain has raised serious concerns not only for the environment but also for human health. This study aimed to investigate the impact of surface properties on the performance of seven distinct membrane types utilized in nanofiltration (NF), reverse osmosis (RO) and forward osmosis (FO) processes in eliminating multiple pesticides from spiked water. Out of the membranes tested, two are self-fabricated RO membranes while the rest are commercially available membranes. Our results revealed that the self-fabricated RO membranes performed better than other commercial membranes (e.g., SW30XLE, NF270, Duracid and FO) in rejecting the targeted pesticides by achieving at least 99% rejections regardless of the size of pesticides and their log Kow value. Despite the marginally lower water flux exhibited by the self-fabricated membrane compared to the commercial BW30 membrane, its exceptional ability to reject both mono- and divalent salts renders it more apt for treating water sources containing not only pesticides but also various dissolved ions. The enhanced performance of the self-fabricated RO membrane is mainly attributed to the presence of a hydrophilic interlayer (between the polyamide layer and substrate) and the incorporation of hydrophilic nanosheets in tuning its surface characteristics. The findings of the work provide insight into the importance of membrane surface modification for the application of not only the desalination process but also for the removal of contaminants of emerging concern.


Asunto(s)
Filtración , Membranas Artificiales , Ósmosis , Plaguicidas , Contaminantes Químicos del Agua , Purificación del Agua , Plaguicidas/análisis , Plaguicidas/química , Plaguicidas/aislamiento & purificación , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Filtración/métodos , Interacciones Hidrofóbicas e Hidrofílicas
12.
Chemosphere ; 357: 142042, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38621490

RESUMEN

The presence of dissolved organic nitrogen (DON) in stormwater treatment processes is a continuous challenge because of the intertwined nature of its decomposition, bioavailability, and biodegradability and its unclear molecular characteristics. In this paper, 21 T Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) in combination with quantitative polymerase chain reaction was applied to elucidate the molecular change of DON and microbial population dynamics in a field-scale water filtration system filled with two specialty adsorbents for comparison in South Florida where the dry and wet seasons are distinctive annually. The adsorbents included CPS (clay-perlite and sand sorption media) and ZIPGEM (zero-valent iron and perlite-based green environmental media). Our study revealed that seasonal effects can significantly influence the dynamic characteristics and biodegradability of DON. The microbial population density in the filter beds indicated that three microbial species in the nitrogen cycle were particularly thrived for denitrification, dissimilatory nitrate reduction to ammonium, and anaerobic ammonium oxidation via competition and commensalism relationships during the wet season. Also, there was a decrease in the compositional complexity and molecular weight of the DON groups (CnHmOpN1, CnHmOpN2, CnHmOpN3, and CnHmOpN4), revealed by the 21 T FT-ICR MS bioassay, driven by a microbial population quantified by polymerase chain reaction from the dry to the wet season. These findings indirectly corroborate the assumption that the metabolism of microorganisms is much more vigorous in the wet season. The results affirm that the sustainable materials (CPS and ZIPGEM) can sustain nitrogen removal intermittently by providing a suitable living environment in which the metabolism of microbial species can be cultivated and enhanced to facilitate physico-chemical nitrogen removal across the two types of green sorption media.


Asunto(s)
Filtración , Nitrógeno , Nitrógeno/metabolismo , Filtración/métodos , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Biodegradación Ambiental , Desnitrificación , Adsorción , Microbiota , Florida , Óxido de Aluminio/química , Eliminación de Residuos Líquidos/métodos
13.
Carbohydr Polym ; 336: 122133, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38670771

RESUMEN

Using respiratory protective equipment is one of the relevant preventive measures for infectious diseases, including COVID-19, and for various occupational respiratory hazards. Because experienced discomfort may result in a decrease in the utilization of respirators, it is important to enhance the material properties to resolve suboptimal usage. We combined several technologies to produce a filtration material that met requirements set by a cross-disciplinary interview study on the usability of protective equipment. Improved breathability, environmental sustainability, and comfort of the material were achieved by electrospinning poly(ethylene oxide) (PEO) nanofibers on a thin foam-formed fabric from regenerated cellulose fibers. The high filtration efficiency of sub-micron-sized diethylhexyl sebacate (DEHS) aerosol particles resulted from the small mean segment length of 0.35 µm of the nanofiber network. For a particle diameter of 0.6 µm, the filtration efficiency of a single PEO layer varied in the range of 80-97 % depending on the coat weight. The corresponding pressure drop had the level of 20-90 Pa for the airflow velocity of 5.3 cm/s. Using a multilayer structure, a very high filtration efficiency of 99.5 % was obtained with only a slightly higher pressure drop. This opens a route toward designing sustainable personal protective media with improved user experience.


Asunto(s)
Celulosa , Filtración , Nanofibras , Celulosa/química , Celulosa/análogos & derivados , Filtración/métodos , Nanofibras/química , Humanos , COVID-19/prevención & control , Polietilenglicoles/química , Dispositivos de Protección Respiratoria , Tamaño de la Partícula , SARS-CoV-2 , Aerosoles/química
14.
Chemosphere ; 356: 141958, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38608775

RESUMEN

In water treatment processes (WTPs), artificial intelligence (AI) based techniques, particularly machine learning (ML) models have been increasingly applied in decision-making activities, process control and optimization, and cost management. At least 91 peer-reviewed articles published since 1997 reported the application of AI techniques to coagulation/flocculation (41), membrane filtration (21), disinfection byproducts (DBPs) formation (13), adsorption (16) and other operational management in WTPs. In this paper, these publications were reviewed with the goal of assessing the development and applications of AI techniques in WTPs and determining their limitations and areas for improvement. The applications of the AI techniques have improved the predictive capabilities of coagulant dosages, membrane flux, rejection and fouling, disinfection byproducts (DBPs) formation and pollutants' removal for the WTPs. The deep learning (DL) technology showed excellent extraction capabilities for features and data mining ability, which can develop an image recognition-based DL framework to establish the relationship among the shapes of flocs and dosages of coagulant. Further, the hybrid techniques (e.g., combination of regression and AI; physical/kinetics and AI) have shown better predictive performances. The future research directions to achieve better control for WTPs through improving these techniques were also emphasized.


Asunto(s)
Inteligencia Artificial , Agua Potable , Floculación , Purificación del Agua , Purificación del Agua/métodos , Agua Potable/química , Desinfección/métodos , Filtración/métodos , Contaminantes Químicos del Agua/análisis , Aprendizaje Automático , Adsorción
15.
Water Res ; 256: 121617, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38642535

RESUMEN

The traditional electrochemical descaling process exhibits drawbacks, including low OH- utilization efficiency, constrained cathode deposition area, and protracted homogeneous precipitation time. Consequently, this study introduces a novel membrane-free electrochemical separation-filtering crystallization (MFES-FC) coupling process to treat circulating cooling water (CCW). In the membrane-free electrochemical separation (MFES) system, OH- is rapidly extracted by pump suction from the porous cathode boundary layer solution, preventing neutralization with H+, thereby enhancing the removal of Ca2+ and Mg2+. Experimental results indicate that the pH of the pump suction water can swiftly increase from 8.13 to 11.42 within 10 min. Owing to the high supersaturation of the pump suction water, this study couples the MFES with a filtration crystallization (FC) system that employs activated carbon as the medium. This approach captures scale particles to enhance water quality and expedites the homogeneous precipitation of hardness ions, shortening the treatment time while further augmenting the removal rate. After the MFES-FC treatment, the single-pass removal rates for total hardness, Ca2+ hardness, Mg2+ hardness, and alkalinity in the effluent reached 92 %, 97 %, 64 %, and 67 %, respectively, with turbidity of 3 NTU, current efficiency of 86.6 %, and energy consumption of 7.19 kWh·kg-1 CaCO3. This coupling process facilitates an effective removal of hardness and alkalinity at a comparatively low cost, offering a new reference and inspiration for advancements in electrochemical descaling technology.


Asunto(s)
Cristalización , Purificación del Agua , Purificación del Agua/métodos , Filtración/métodos , Técnicas Electroquímicas , Agua/química , Concentración de Iones de Hidrógeno
16.
Environ Pollut ; 349: 123903, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38599272

RESUMEN

To investigate watershed remediation within a Total Maximum Daily Load program, this study examined the field-scale filtration performance of two specialty absorbents. The goal was to simultaneously remove nutrients and biological pollutants along Canal 23 (C-23) in the St. Lucie River Basin, Florida. The filtration system installed in the C-23 river corridor was equipped with either clay-perlite with sand sorption media (CPS) or zero-valent iron and perlite green environmental media (ZIPGEM). Both media were formulated with varying combinations of sand, clay, perlite, and/or recycled iron based on distinct recipes. In comparison with CPS, ZIPGEM exhibited higher average removal percentages for nutrients. Findings indicated that ZIPGEM could remove total nitrogen up to 49.3%, total Kjeldahl nitrogen up to 67.1%, dissolved organic nitrogen (DON) up to 72.9%, total phosphorus up to 79.6%, and orthophosphate up to 73.2%. Both ZIPGEM and CPS demonstrated similar efficiency in eliminating biological pollutants, such as E. coli (both media exhibiting an 80% removal percentage) and chlorophyll a (both media achieving approximately 95% removal). Seasonality effects were also evident in nutrient removal efficiencies, particularly in the case of ammonia nitrogen; the negative removal efficiency of ammonia nitrogen from the fifth sampling event could be attributed to processes such as photochemical ammonification, microbial transformation, and mineralization of DON in wet seasons. Overall, ZIPGEM demonstrated a more stable nutrient removal efficiency than CPS in the phase of seasonal changes.


Asunto(s)
Restauración y Remediación Ambiental , Filtración , Nitrógeno , Fósforo , Dióxido de Silicio , Contaminantes Químicos del Agua , Filtración/métodos , Contaminantes Químicos del Agua/análisis , Restauración y Remediación Ambiental/métodos , Restauración y Remediación Ambiental/instrumentación , Florida , Purificación del Agua/métodos , Ríos/química , Óxido de Aluminio/química , Escherichia coli , Clorofila A , Arcilla/química , Hierro/química
18.
Bioresour Technol ; 400: 130650, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38570099

RESUMEN

Illustrating the biodegradation processes of multi-component volatile organic compounds (VOCs) will expedite the implication of biotechnology in purifying industrial exhaust. Here, performance shifts of microbial fuel cell and biotrickling filter combined system (MFC-BTF) are investigated for removing single and dual components of toluene and benzene. Synchronous removal of toluene (95 %) and benzene (97 %) are achieved by MFC-BTF accompanied with the output current of 0.41 mA. Elevated content of extracellular polymeric substance facilitates the mass transfer of benzene with the presence of toluene. Strains of Bacteroidota, Proteobacteria and Chloroflexi contribute to the removal of dual components VOCs. Empty bed reaction time and the VOCs concentration are the important factors influencing their dissolution in the system. The biodegradation of toluene and benzene proceeds with 2-hydroxymuconic semialdehyde and o-hydroxybenzoic acid as the main intermediates. These results provide a comprehensive understanding of multi-component VOCs removal by MFC-BTF and guide the system design, optimization, and scale-up.


Asunto(s)
Benceno , Biodegradación Ambiental , Fuentes de Energía Bioeléctrica , Tolueno , Tolueno/metabolismo , Benceno/metabolismo , Filtración/métodos , Compuestos Orgánicos Volátiles/metabolismo , Gases/metabolismo
19.
Chemosphere ; 356: 141885, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38575084

RESUMEN

The effects of the operating conditions, including the applied pressure, feed organic concentration, and recirculation flowrate along the TiO2-coated ceramic membrane, on the normalized membrane permeability and organic removal efficiency were systematically investigated by operating a photocatalytic membrane reactor (PMR). Response surface methodology (RSM) was conducted to better understand the interactive effect of operational conditions as well as their individual and combined effects to control membrane performance. Our results showed that the applied pressure and feed organic concentration, as single parameter, affected the normalized membrane permeability and organic removal efficiency more dominantly than the recirculation flowrate. The polynomial performance equations generated by RSM successfully predicted the membrane performance of the PMR. The responses to the normalized membrane permeability and organic removal efficiency with respect to the operational conditions were less sensitive to any combination of operational conditions than to their individual impacts. The combined effects of the operating conditions were less pronounced in promoting the catalytic performance of organic contaminants on the TiO2 surface. Our RSM analysis based on experimental observations designed by Box-Behnken Design (BBD) suggested that 1.3 bar of applied pressure, 44 mg/L of feed organic dye concentration and 0.8 L/min as recirculation flowrate as optimum conditions achieved more than 98% of organic removal efficiency and less than 5% of decline in normalized membrane permeability. This research shows that the RSM provides effective tool to optimize operational conditions to determine fouling rate and organic removal in PMR.


Asunto(s)
Cerámica , Filtración , Membranas Artificiales , Titanio , Cerámica/química , Filtración/métodos , Titanio/química , Catálisis , Hidrodinámica , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Eliminación de Residuos Líquidos/métodos , Permeabilidad
20.
Chemosphere ; 356: 141882, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38582163

RESUMEN

Microfiltration (MF) using membranes with a mean pore size smaller than 0.45 µm has generally been used for particle removal from water, given that materials larger and smaller than 0.45 µm are regarded as particulates and dissolved organic matter (DOM), respectively. It is also the case for removing small-size microplastics (MPs). However, given their sizes (ca. 1 µm), there is room for further improvement of the productivity (i.e., water flux) in the pore size range of 0.45-1 µm on the condition that the removal rate is maintained. With this in mind, MF's water flux and removal rate were tested using seven different MF membranes, and the right pore, with the size of 0.8 µm, was found for MP removal, which is called near DOM (NDOM) MF. In the filtration test using polystyrene surrogate beads with an average particle diameter of 1.20 µm, NDOM MF exhibited a 1.7 to 13 times higher permeate flux than the conventional MF using 0.1, 0.2, and 0.45 µm membranes while maintaining a higher removal rate than 2 log. The excellent removal rate of the NDOM MF was attributable to the following three factors: (1) smaller mean pore size than the average particle diameter, (2) particle screening effect enhanced by the secondary layer formed by surface deposition, and (3) 3D mesh sublayer structure favorable for capturing penetrated particles. Furthermore, the outstanding filtration performance also appeared in a low-temperature (< 10°C) process, demonstrating that NDOM MF is feasible independently of temperature. Additionally, in constant flux filtration, NDOM MF demonstrated the long-term feasibility by lowering the transmembrane pressure and specific filtration energy by more than 2 times.


Asunto(s)
Filtración , Microplásticos , Contaminantes Químicos del Agua , Purificación del Agua , Microplásticos/análisis , Filtración/métodos , Purificación del Agua/métodos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química , Membranas Artificiales , Estudios de Factibilidad , Tamaño de la Partícula
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