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1.
Nano Lett ; 24(8): 2629-2636, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38349527

RESUMO

Atmospheric water harvesting (AWH) has been broadly exploited to meet the challenge of water shortage. Despite the significant achievements of AWH, the leakage of hydroscopic salt during the AWH process hinders its practical applications. Herein, inspired by the unique selective permeability of the phospholipid bilayer, a sandwich structural (hydrophobic-hydrophilic-hydrophobic) polyacrylonitrile nanofibrous membrane (San-PAN) was fabricated for AWH. The hydrophilic inner layer loaded with LiCl could capture water from the air. The hydrophobic microchannels in the outer layer could selectively allow the free transmission of gaseous water molecules but confine the hydroscopic salt solution in the hydrophilic layer, achieving continuous and recyclable water sorption/desorption. As demonstrated, the as-prepared AWH devices presented high-efficient adsorption kinetics from 1.66 to 4.08 g g-1 at 30% to 90% relative humidity. Thus, this work strengthens the understanding of the water transmission process along microchannels and provides insight into the practical applications of AWH.

2.
Nano Lett ; 24(13): 3858-3865, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38437505

RESUMO

Moisture-capturing hydrogels have emerged as attractive sorbent materials capable of converting ambient humidity into liquid water. Recent works have demonstrated exceptional water capture capabilities of hydrogels while simultaneously exploring different strategies to accelerate water capture and release. However, on the material level, an understanding of the intrinsic transport properties of moisture-capturing hydrogels is currently missing, which hinders their rational design. In this work, we combine absorption and desorption experiments of macroscopic hydrogel samples in pure vapor with models of water diffusion in the hydrogels to demonstrate the first measurements of the intrinsic water diffusion coefficient in hydrogel-salt composites. Based on these insights, we pattern hydrogels with micropores to significantly decrease the required absorption and desorption times by 19% and 72%, respectively, while reducing the total water capacity of the hydrogel by only 4%. Thereby, we provide an effective strategy toward hydrogel material optimization, with a particular significance in pure-vapor environments.

3.
Small ; : e2400265, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38660825

RESUMO

Two titanium-based MOFs MIL-125 and MIL-125_NH2 are synthesized and characterized using high-temperature powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), N2 sorption, Fourier transformed infrared spectroscopy (FTIR), Raman spectroscopy, ultraviolet-visible spectroscopy (UV-Vis), and electron paramagnetic resonance (EPR). Stable up to 300 °C, both compounds exhibited similar specific surface areas (SSA) values (1207 and 1099 m2 g-1 for MIL-125 and MIL-125_NH2, respectively). EPR signals of Ti3+ are observed in both, whith MIL-125_NH2 also showing ─NH2 ●+ signatures. Both MOFs efficiently adsorbed iodine in continuous gas flow over five days, with MIL-125 trapping 1.9 g.g-1 and MIL-125_NH2 trapping 1.6 g.g-1. MIL-125_NH2 exhibited faster adsorption kinetics due to its smaller band gap (2.5 against 3.6 eV). In situ Raman spectroscopy conducted during iodine adsorption revealed signal evolution from "free" I2 to "perturbed" I2, and I3 -. TGA and in situ Raman desorption experiments showed that ─NH2 groups improved the stabilization of I3 - due to an electrostatic interaction with NH2 ●+BDC radicals. The Albery model indicated longer lifetimes for iodine desorption in I2@MIL-125_NH2, attributed to a rate-limiting step due to stronger interaction between the anionic iodine species and the ─NH2 ●+ radicals. This study underscores how MOFs with efficient charge separation and hole-stabilizer functional groups enhance iodine stability at higher temperatures.

4.
Small ; : e2400420, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38751057

RESUMO

Global water scarcity is leading to increasingly tense competition across populations. In order to complement the largely fast-depleting fresh water sources and mitigate the challenges generated by brine discharge from desalination, atmospheric water harvesting (AWH) has emerged to support long-term water supply. This work presents a novel alginate-based hybrid material comprised of porous silico-aluminophosphate-34 (SAPO-34) as fast-transport channel medium as well as hydrophilicity and stability enhancer, and graphene-based sheets as light absorber for solar-enabled evaporation, both optimally incorporated in an alginate matrix, resulting in a composite sorbent capable of harvesting water from the atmosphere with a record intake of up to 6.85 gw gs -1. Natural sunlight is solely used to enable desorption achieving increase of the temperature of the developed network up to 60 °C and resulting in release of the sorbed water, with impurities content well below the World Health Organization (WHO) upper limits. After 30 cycles of sorption and desorption, the composite hydrogel displayed unchanged water uptake and stability. This work provides an impactful perspective toward sustainable generation of water from humidity without external energy consumption supporting the emergence of alternative water production solutions.

5.
Small ; : e2401167, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528426

RESUMO

Covalent organic frameworks (COFs) are promising iodine adsorbents. For improved performances, it is critical and essential to fundamentally understand the underlying mechanism. Here, using the operando dark-field optical microscopy (DFM) imaging technique, the observation of an extraordinary structure shrinkage of 2D triphenylbenzene (TPB)-dimethoxyterephthaldehyde (DMTP)-COF upon the adsorption of I2 vapor at the single-particle resolution is reported. Combining single-particle DFM imaging with other experimental and theoretical methods, it is revealed that the shrinkage mechanism of the TPB-DMTP-COF is attributed to the I2 sorption-induced synchronous skeleton-pore interactions. The redox reaction of I2 and TPB-DMTP-COF yields some cationic skeletons and I3 - species, which triggers the multi-directional halogen-bonding interactions of I2 and I3 - as well as strong cation-π interactions between neutral and cationic skeletons, accompanying the synchronous in-plane skeleton shrinking in the xy plane and compact out-of-plane layer packing in the z-direction. This understanding of the synchronous action between the skeleton and pore breaks the perspective on the structure robustness of 2D COFs with excellent stability during the I2 uptake, which offers pivotal guidance for the rational design and creation of advanced microporous adsorbents.

6.
Chemistry ; : e202401551, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38779975

RESUMO

In recent years, European Union member states have hastened energy policy deliberations to address supply and sustainability concerns, placing a significant emphasis on nuclear energy as a means to achieve decarbonization goals. However, despite its significant role in power generation, nuclear energy faces significant challenges linked to fuel reprocessing and waste disposal, that hinder its broader expansion. In this context, the separation of technetium represents a concerning issue. Indeed, technetium's catalytic activity can impede the extraction of uranium, neptunium, and plutonium, affecting waste reprocessing efficiency. Additionally, the stable form of technetium in aerobic conditions, pertechnetate (TcO4 -), poses risks of groundwater contamination due to its mobility and solubility. Hence, sensing and separation of TcO4 - is imperative for both nuclear fuel processing and minimising radioactive contamination in the environment. However, the binding of TcO4 - and its separation from contaminated solutions present challenges due to the acidic (or basic) waste components and the high ionic strength in real matrices. Supramolecular chemists have addressed these issues by designing receptors inspired by molecular recognition principles. This article explores recent advancements and future directions in TcO4 - sensing and separation (using extraction and sorption) with a focus on molecular hosts. Metal-organic receptors will also be discussed.

7.
Chemistry ; 30(4): e202302709, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-37823681

RESUMO

An exciting direction in metal-organic frameworks involves the design and synthesis of flexible structures which can reversibly adapt their structure when triggered by external stimuli. Controlling the extent and nature of response in such solids is critical in order to develop custom dynamic materials for advanced applications. Towards this, it is highly important to expand the diversity of existing flexible MOFs, generating novel materials and gain an in-depth understanding of the associated dynamic phenomena, eventually unlocking key structure-property relationships. In the present work, we successfully utilized reticular chemistry for the construction of two novel series of highly crystalline, flexible rare-earth MOFs, RE-thc-MOF-2 and RE-teb-MOF-1. Extensive single-crystal to single-crystal structural analyses coupled with detailed gas and vapor sorption studies, shed light onto the unique responsive behavior. The development of these series is related to the reported RE-thc-MOF-1 solids which were found to display a unique continuous breathing and gas-trapping property. The synthesis of RE-thc-MOF-2 and RE-teb-MOF-1 materials represents an important milestone as they provide important insights into the key factors that control the responsive properties of this fascinating family of flexible materials and demonstrates that it is possible to control their dynamic behavior and the associated gas and vapor sorption properties.

8.
Biopolymers ; 115(4): e23580, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38622846

RESUMO

The purpose of this study was to examine the effect of maltodextrin addition on the physical stability of powdered green peas. The evaluation of the physical state of the material was based on the equilibrium water content of the monolayer (Xm) and the glass transition temperatures of the powders at room temperature (Tg) and in the frozen state (Tg'). Graphical sorption characteristic at 25°C was determined using static-gravimetric method while capacity of the monolayer values was calculated from the mathematical GAB model. Differential scanning calorimetry was carried out in order to determine glass transition lines and freezing curves which combine together were used to plot state diagrams. Relationship between Tg and solid content were shown by using Gordon-Taylor model. Freezing data were modeled employing the Clausius-Clapeyron equation and its development-Chen model. Sorption isotherms showed sigmoidal shape characteristic for high-molecular weight materials. Monolayer moisture content varied between 0.047 and 0.106 g water/g solids. The glass transition temperature of anhydrous green peas increased in from 89.9 to 175.6°C while Tg' value changed from -43.4 to -26.6°C to as a result of 75% polysaccharide addition. The ultimate maximum-freeze-concentration conditions of the powders were observed in range from 0.783 to 0.814 g solids/g sample. Monolayer capacity, Tg and Tg' values increased with increasing maltodextrin amount in the sample which indicates that the addition of starch hydrolysate has a beneficial effect on the stability of powders stored frozen and at room temperature.


Assuntos
Varredura Diferencial de Calorimetria , Polissacarídeos , Pós , Polissacarídeos/química , Pós/química , Temperatura de Transição , Congelamento , Água/química , Temperatura
9.
Chemphyschem ; 25(4): e202300817, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38100298

RESUMO

Precious metals are used in many branches of industries. Due to their rarity and diminishing natural resources, more and more new methods are being sought to recover them from secondary sources, which can be electronic waste or spent car exhaust converters. This paper presents the research on the recovery of precious metals from chloride solutions using the Aliquat 336-impregnated Lewatit VP OC 1026 sorbent. The study used a warm impregnation method without toxic solvents, which is beneficial for the environment. The maximal sorption capacities obtained for model solutions in 0.1 M HCl were: 95.6 mg/g for gold, 38.2 mg/g for palladium, and 36.2 mg/g for platinum. There were studied: kinetics and thermodynamics of sorption, as well as amounts of the sorbent, effects of phase contact time and HCl concentration on the sorption of precious metals. Positive values of enthalpy change ΔH° validate that the process is endothermic. The research was also carried out on a real leaching solution obtained by digesting a spent catalytic converter, containing small amounts of platinum group metals. Desorption of precious metal ions was conducted using 1 M thiourea in 1 M hydrochloric acid. The obtained impregnated sorbent proved to be effective for sorption of Au(III), Pd(II), Pt(IV) ions.

10.
Chemphyschem ; 25(4): e202300812, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38227375

RESUMO

Two series of hydrogels based on acrylamide and its copolymers with acrylonitrile and acrylic acid were synthesized by two cross-linking methods - chemical (using N,N'-methylene bis-acrylamide) and physical (using montmorillonite (MMT)) ones. The structure of the gels was characterized by Fourier Transform Infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The swelling and sorption properties were analyzed as a function of both the monomer composition and the cross-linking method. The shift of the band corresponding to Si-O (995-1030 cm-1 ) confirmed the formation of intercalation structures for MMT-cross-linked gels. Moreover, physically cross-linked gels demonstrated a non-monotonic dependence of the swelling degree on the MMT concentration, and acrylamide-acrylic acid copolymer MMT-cross-linked gels showed pH sensitivity and the highest swelling degree of 150 g/g. The highest sorption capacity towards cadmium(II) ions was demonstrated by acrylamide-acrylic acid copolymer gels, both covalently cross-linked (30 mg/g) and MMT-cross-linked (8.9 mg/g).

11.
Mol Pharm ; 21(5): 2484-2500, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38647432

RESUMO

Excipients are ubiquitous in pharmaceutical products, and often, they can also play a critical role in maintaining product quality. For a product containing a moisture-sensitive drug, moisture can be deleterious to the product stability during storage. Therefore, using excipients that interact with moisture in situ can potentially alleviate product stability issues. In this study, the interactive behavior of starch with moisture was augmented by coprocessing maize starch with sodium chloride (NaCl) or magnesium nitrate hexahydrate [Mg(NO3)2·6H2O] at different concentrations (5 and 10%, w/w). The effect of the formulation on drug stability was assessed through the degradation of acetylsalicylic acid, which was used as the model drug. The results showed that coprocessing of the starch with either NaCl or Mg(NO3)2·6H2O impacted the number of water molecule binding sites on the starch and how the sorbed moisture was distributed. The coprocessed excipients also resulted in lower drug degradation and lesser changes in tablet tensile strength during post-compaction storage. However, corresponding tablet formulations containing physical mixtures of starch and salts did not yield promising outcomes. This study demonstrated the advantageous concomitant use of common excipients by coprocessing to synergistically mitigate the adverse effects of moisture and promote product stability when formulating a moisture-sensitive drug. In addition, the findings could help to improve the understanding of moisture-excipient interactions and allow for the judicious choice of excipients when designing formulations containing moisture-sensitive drugs.


Assuntos
Estabilidade de Medicamentos , Excipientes , Amido , Comprimidos , Resistência à Tração , Excipientes/química , Amido/química , Comprimidos/química , Água/química , Química Farmacêutica/métodos , Cloreto de Sódio/química , Composição de Medicamentos/métodos , Aspirina/química
12.
Mol Pharm ; 21(6): 2908-2921, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38743928

RESUMO

The physical stability of amorphous solid dispersions (ASDs) is a major topic in the formulation research of oral dosage forms. To minimize the effort of investigating the long-term stability using cost- and time-consuming experiments, we developed a thermodynamic and kinetic modeling framework to predict and understand the crystallization kinetics of ASDs during long-term storage below the glass transition. Since crystallization of the active phrarmaceutical ingredients (APIs) in ASDs largely depends on the amount of water absorbed by the ASDs, water-sorption kinetics and API-crystallization kinetics were considered simultaneously. The developed modeling approach allows prediction of the time evolution of viscosity, supersaturation, and crystallinity as a function of drug load, relative humidity, and temperature. It was applied and evaluated against two-year-lasting crystallization experiments of ASDs containing nifedipine and copovidone or HPMCAS measured in part I of this work. We could show that the proposed modeling approach is able to describe the interplay between water sorption and API crystallization and to predict long-term stabilities of ASDs just based on short-term measurements. Most importantly, it enables explaining and understanding the reasons for different and sometimes even unexpected crystallization behaviors of ASDs.


Assuntos
Cristalização , Água , Cristalização/métodos , Água/química , Cinética , Estabilidade de Medicamentos , Nifedipino/química , Compostos de Vinila/química , Termodinâmica , Pirrolidinas/química , Viscosidade , Química Farmacêutica/métodos , Umidade , Temperatura , Solubilidade , Metilcelulose/química , Metilcelulose/análogos & derivados
13.
Environ Sci Technol ; 58(13): 5987-5995, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38504492

RESUMO

Sorption to activated carbon is a common approach to reducing environmental risks of waterborne perfluorooctanoic acid (PFOA), while effective and flexible approaches to PFOA sorption are needed. Variations in temperature or the use of electrokinetic phenomena (electroosmosis and electromigration) in the presence of external DC electric fields have been shown to alter the contaminant sorption of contaminants. Their role in PFOA sorption, however, remains unclear. Here, we investigated the joint effects of DC electric fields and the temperature on the sorption of PFOA on activated carbon. Temperature-dependent batch and column sorption experiments were performed in the presence and absence of DC fields, and the results were evaluated by using different kinetic sorption models. We found an emerging interplay of DC and temperature on PFOA sorption, which was linked via the liquid viscosity (η) of the electrolyte. For instance, the combined presence of a DC field and low temperature increased the PFOA loading up to 38% in 48 h relative to DC-free controls. We further developed a model that allowed us to predict temperature- and DC field strength-dependent electrokinetic benefits on the drivers of PFOA sorption kinetics (i.e., intraparticle diffusivity and the film mass transfer coefficient). Our insights may give rise to future DC- and temperature-driven applications for PFOA sorption, for instance, in response to fluctuating PFOA concentrations in contaminated water streams.


Assuntos
Fluorocarbonos , Poluentes Químicos da Água , Temperatura , Carvão Vegetal , Adsorção , Fluorocarbonos/análise , Caprilatos , Cinética , Poluentes Químicos da Água/análise
14.
Environ Sci Technol ; 58(12): 5472-5482, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38466321

RESUMO

The fate of selected UV filters (UVFs) was investigated in two soil aquifer treatment (SAT) systems, one supplemented with a reactive barrier containing clay and vegetable compost and the other as a traditional SAT reference system. We monitored benzophenone-3 (BP-3) and its transformation products (TPs), including benzophenone-1 (BP-1), 4,4'-dihydroxybenzophenone (4DHB), 4-hydroxybenzophenone (4HB), and 2,2'-dihydroxy-4-methoxybenzophenone (DHMB), along with benzophenone-4 (BP-4) and avobenzone (AVO) in all involved compartments (water, aquifer sediments, and biofilm). The reactive barrier, which enhances biochemical activity and biofilm development, improved the removal of all detected UVFs in water samples. Among monitored UVFs, only 4HB, BP-4, and AVO were detected in sediment and biofilm samples. But the overall retained amounts were several orders of magnitude larger than those dissolved. These amounts were quantitatively reproduced with a specifically developed simple analytical model that consists of a mobile compartment and an immobile compartment. Retention and degradation are restricted to the immobile water compartment, where biofilm absorption was simulated with well-known compound-specific Kow values. The fact that the model reproduced observations, including metabolites detected in the biofilm but not in the (mobile) water samples, supports its validity. The results imply that accumulation ensures significant biodegradation even if the degradation rates are very low and suggest that our experimental findings for UVFs and TPs can be extended to other hydrophobic compounds. Biofilms act as accumulators and biodegraders of hydrophobic compounds.


Assuntos
Solo , Poluentes Químicos da Água , Porosidade , Protetores Solares/análise , Benzofenonas/química , Água/química , Poluentes Químicos da Água/análise
15.
Environ Sci Technol ; 58(16): 7133-7143, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38587400

RESUMO

Reactions of mineral surfaces with dissolved metal ions at far-from-equilibrium conditions can deviate significantly from those in near-equilibrium systems due to steep concentration gradients, ion-surface interactions, and reactant transport effects that can lead to emergent behavior. We explored the effect of dissolved Pb2+ on the dissolution rate and topographic evolution of calcite (104) surfaces under far-from-equilibrium acidic conditions (pH 3.7) in a confined single-pass laminar-flow geometry. Operando measurements by digital holographic microscopy were conducted over a range of Pb2+ concentrations ([Pb2+] = 0 to 5 × 10-2 M) and flow velocities (v = 1.67-53.3 mm s-1). Calcite (104) surface dissolution rates decreased with increasing [Pb2+]. The inhibition of dissolution and the emergence of unique topographic features, including micropyramids, variable etch pit shapes, and larger scale topographic patterns, became increasingly apparent at [Pb2+] ≥ 5 × 10-3 M. A better understanding of such dynamic reactivity could be crucial for constructing accurate models of geochemical transport in aqueous carbonate systems.

16.
Anal Bioanal Chem ; 416(15): 3479-3485, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38717624

RESUMO

This Feature Article reports general and more specific aspects about microplastic (MP) contamination in continental and marine waters as well as in terrestrial environment. It describes a critical vision of the analytical methods commonly used for MP characterization and determination, including recommendations on green analytical chemistry (GAC) protocols. Insights into MPs as sorption materials and carriers for a variety of emerging contaminants like pharmaceuticals and pesticides are highlighted. Risks to biota living in aquatic and terrestrial environments and human-health-related effects with specific examples of surface and groundwater used for drinking water sources near contaminated sites like landfills are summarized. Lastly, sustainable solutions for how to improve the analysis and comparison of MP detection at the global level is given, including the need for standardized analytical protocols as well as the performance of additional interlaboratory exercises. Additional recommendations include a global database on MP levels made available to all authors to better compare their data qualitatively with that previously published. Policy and remediation actions on how to reduce and mitigate MP pollution may include different types of actions like an improved waste management and reuse system, the development of bioplastics and new plastic materials, as well as legally binding additional funding to cope with increasing plastic pollution at the global scale.

17.
Environ Res ; 257: 119353, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38844033

RESUMO

Herein, tannic acid-tethered cellulose was developed as an efficient and selective sorbent for Mn2⁺ removal from aqueous solutions. The modified cellulose was characterized through scanning electron microscopy, infrared spectroscopy, and elemental analyses. Sorption performance was evaluated using various parameters, including pH, initial Mn2⁺ concentration, contact time, and the presence of interfering ions. Results indicated that Mn2⁺ removal was highly pH-dependent, with removal efficiency increasing from 8% at pH 2 to99% at pH 9, achieving a remarkable 99% removal rate within only 30 min, highlighting the rapidity of the cellulose sorption kinetics. The results of isotherm studies confirmed that the sorption conformed to the Langmuir model with a monolayer sorption mechanism. Using a sorbent dose of 0.05 g, 99% of Mn2⁺ could be effectively eliminated from water, achieving a maximum sorption capacity of 32.2 mg/g dry-sorbent. The modified cellulose could be effectively regenerated using 0.5-M HCl or 0.1-M H2SO4, with no considerable deterioration in sorption performance after three sorption-regeneration cycles. The presence of Na⁺ and K⁺ had minimal impact on Mn2⁺ removal, whereas the presence of Ca2⁺ and Mg2⁺ at low concentrations facilitated moderate-level Mn2⁺ removal.

18.
Environ Res ; 258: 119430, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38885826

RESUMO

A silica gel-modified borage biochar (BB@Si) was first produced and used as a binding agent for potentially hazardous Ni2+ ions in aqueous systems. The recommended biochar was more effective in eliminating Ni2+ than pristine biochar (BB). Its maximum qm could reach up to 1.39 × 10-3 mol/g at 30 °C, and sorption isotherms showed that the Langmuir model could more accurately define its sorption behavior. The Dubinin-Radushkevich isotherm also revealed that the average sorption energy ranged from 11.00 to 11.14 kJ/mol. Zeta potential tests, SEM images, and FT-IR scans confirmed the interactions between BB@Si and Ni2+ ions. Dynamic flow treatment studies showed high uptake effectiveness when the flow rate and amount of BB@Si were suitable. Nickel desorption yield of around 80% from BB@Si was noted with 0.01 M HCl. The BB@Si column's breakthrough and exhausted points were identified to be 45 and 352 min, respectively. Its maximum exhaustion capacity value was determined to be 52.73 mg/g. Ni2+ removal from the actual wastewater sample exceeded 75%. The resulting outcomes imply the immense potential of employing BB@Si in the treatment of Ni2+- contaminated aqueous systems.

19.
Environ Res ; 244: 117898, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38092242

RESUMO

Sorption by soil is the fundamental basis for environment fate of hydrophobic organic contaminants (HOCs), which varies significantly depending on diverse properties of soils. Therefore, a generalized approach to predict HOC sorption by soils is required. In this study, 488 data points were extracted from references and adopted to develop models for estimating the sorption capacities of phenanthrene in soils using six different machine learning (ML) approaches. The extreme gradient boosting (XGBT) model demonstrated the most favorable performance, achieving a coefficient of determination of 0.91 and root-mean-square errors of 0.24 for the testing dataset. The XGBT model's performance was further demonstrated by comparing with experimental data from batch sorption tests conducted on 20 soil samples collected from 17 provinces of China. The differences between the predicted values and the experimental values were statistically equal to zero (p = 0.14). Leveraging the XBGT model together with soil properties from the Harmonized World Soil Database, the distribution of sorption capacities in Chinese soils was successfully depicted on a national scale. This research is expected to contribute to a deeper understanding of the migration of persistent organic pollutants in terrestrial system. Furthermore, the established model holds implications for more precise and scientific soil environmental management.


Assuntos
Fenantrenos , Poluentes do Solo , Solo , Adsorção , Poluentes do Solo/análise , Interações Hidrofóbicas e Hidrofílicas , Fenantrenos/química
20.
Environ Res ; 257: 119231, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38797468

RESUMO

The persistent water treatment and separation challenge necessitates innovative and sustainable advances to tackle conventional and emerging contaminants in the aquatic environment effectively. Therefore, a unique three-dimensional (3D) network composite film (BNC-KC) comprised of bacterial nanocellulose (BNC) incorporated nano-kaolinite clay particles (KC) was successfully synthesized via an in-situ approach. The microscopic characterization of BNC-KC revealed an effective integration of KC within the 3D matrix of BNC. The investigated mechanical properties of BNC-KC demonstrated a better performance compared to BNC. Thereafter, the sorption performance of BNC-KC films towards basic blue 9 dye (Bb9) and norfloxacin (NFX) antibiotic from water was investigated. The maximum sorption capacities of BNC-KC for Bb9 and NFX were 127.64 and 101.68 mg/g, respectively. Mechanistic studies showed that electrostatic interactions, multi-layered sorption, and 3D structure are pivotal in the NFX/Bb9 sorption process. The intricate architecture of BNC-KC effectively traps molecules within the interlayer spaces, significantly increasing sorption efficiency. The distinctive structural configuration of BNC-KC films effectively addressed the challenges of post-water treatment separation while concurrently mitigating waste generation. The environmental evaluation, engineering, and economic feasibility of BNC-KC are also discussed. The cost estimation assessment of BNC-KC revealed the potential to remove NFX and Bb9 from water at an economically viable cost.

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