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1.
Chemosphere ; : 142849, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39009093

RESUMO

The present study focuses on the application of fungal-based microbial fuel cells (FMFC) for the degradation of organic pollutants including Acetaminophen (APAP), Para-aminophenol (PAP), Sulfanilamide (SFA), and finally Methylene Blue (MB). The objective is to investigate the patterns of degradation (both individually and as a mixture solution) of the four compounds in response to fungal metabolic processes, with an emphasis on evaluating the possibility of generating energy. Linear Sweep Voltammetry (LSV) has been used for electrochemical analysis of the targeted compounds on a Glassy Carbon Electrode (GCE). A dual chamber MFC has been applied wherein the cathodic compartment, the reduction reaction of oxygen was catalyzed by an elaborated biofilm of Trametes trogii, and the anodic chamber consists of a mixed solution of 200 mg L-1 APAP, PAP, MB, and SFA in 0.1 M PBS and an elaborated biofilm of Trichoderma harzianum. The obtained results showed that all the tested molecules were degraded over time by the Trichoderma harzianum. The biodegradation kinetics of all the tested molecules were found to be in the pseudo-first-order. The results of half-lives and the degradation rate reveal that APAP In its individual form degrades relatively slower (0.0213 h-1) and has a half-life of 33h compared to its degradation in a mixed solution with a half-life of 20 h. SFA showed the longest half-life in the mixed condition (98h) which is the opposite of its degradation as individual molecules (20h) as the fastest molecule compared to other pollutants. The degradation rate constant also supports these findings. The maximum power density of the developed MFC dropped from 0.65 mW m-2 to 0.32 mW m-2 after 45.5 h, showing that the decrease of the residual concentration of molecules in the anodic compartment leads to the decrease of the MFC performance.

2.
Chemosphere ; 305: 135466, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35760125

RESUMO

Corrosion is a major problem resulting from acid gases found in natural gas being transported in pipelines. To solve this problem, high aspect ratio h-BN nanosheets have been incorporated and are properly assimilated in the CA matrix, this led to an increase in tortuous path of flow for the gas resulting in smooth, dense membrane samples causing exceptional permeability reduction. Hexagonal Boron Nitride (h-BN) nanosheets have been synthesized and incorporated into cellulose acetate (CA) matrix using solution casting method. Nanosheets of various sizes, separated by varying centrifugation speeds (i.e. 500 rpm, 700 rpm, 1500 rpm, 2000 rpm and 2500 rpm), have been prepared and used for our work. The resulting nanocomposites, having thickness ranging between 40 and 60 µm, were then tested for CO2 gas permeability reduction using both short-term (8 h) tests as well as long-term (72-h tests). As a result of these tests, a maximum CO2 permeability reduction of 99.84% is found with a minimum CO2 permeability of 3.25 barrer. For dimensional analysis of both nanosheets and nanocomposites, scanning electron microscopy (SEM) analysis is used. For verifying the presence of the required functional groups in our synthesized samples, FT-IR spectroscopy is used. Moreover, to confirm the presence of crystalline phases, X-ray Diffraction (XRD) analysis is used. Also, tensile testing is used to analyze the mechanical robustness and it was found that nanocomposite samples exhibited higher tensile strength as compared to pristine samples. Furthermore, tribological property analysis was also carried out for adhesion testing of polymeric material with steel.


Assuntos
Dióxido de Carbono , Nanocompostos , Compostos de Boro/química , Gases , Nanocompostos/química , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Int J Anal Chem ; 2022: 9994639, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35310878

RESUMO

Nickel(II) tetrasulfonated phthalocyanine (p-NiTSPc)-modified carbon fiber microelectrode (CFME) was used for the first time to investigate the electrochemical quantification of diuron in an agrochemical formulation. The surface morphology and elementary analysis of unmodified carbon fiber microelectrode (CFME) and p-NiTSPc-CFME were performed using atomic force microscopy (AFM) and energy dispersive X-ray spectroscopy (EDX), respectively. Cyclic voltammetry (CV) was used to investigate the electrochemical behaviour of diuron, while square wave voltammetry (SWV) was used for quantitative analysis of diuron. Upon variation of some key analytical parameters, a calibration curve was plotted in the concentration range from 21.450 to 150.150 µM, leading to a detection limit (DL) of 8.030 µM mg/L (3.3σ/m) and a limit of quantification (LQ) of 20.647 µM mg/L. The fabricated p-NiTSPc-CFME was successfully applied for quality control in a commercialized formulation of diuron. The standard additional method was used, and the recovery rate of diuron was found to be 98.4%.

4.
Anal Bioanal Chem ; 408(21): 5895-5903, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27349916

RESUMO

The nonpathogenic filamentous fungus Scedosporium dehoogii was used for the first time to study the electrochemical biodegradation of acetaminophen (APAP). A carbon fiber microelectrode (CFME) modified by nickel tetrasulfonated phthalocyanine (p-NiTSPc) and a carbon paste electrode (CPE) modified with coffee husks (CH) were prepared to follow the kinetics of APAP biodegradation. The electrochemical response of APAP at both electrodes was studied by cyclic voltammetry and square wave voltammetry. p-NiTSPc-CFME was suitable to measure high concentrations of APAP, whereas CH-CPE gave rise to high current densities but was subject to the passivation phenomenon. p-NiTSPc-CFME was then successfully applied as a sensor to describe the kinetics of APAP biodegradation: this was found to be of first order with a kinetics constant of 0.11 day(-1) (at 25 °C) and a half-life of 6.30 days. APAP biodegradation by the fungus did not lead to the formation of p-aminophenol (PAP) and hydroquinone (HQ) that are carcinogenic, mutagenic, and reprotoxic (CMR). Graphical Abstract The kinetics of APAP biodegradation, followed by a poly-nickel tetrasulfonated phtalocyanine modified carbon fiber microelectrode.


Assuntos
Acetaminofen/metabolismo , Analgésicos não Narcóticos/metabolismo , Poluentes Ambientais/metabolismo , Scedosporium/metabolismo , Acetaminofen/análise , Analgésicos não Narcóticos/análise , Biodegradação Ambiental , Carbono/química , Técnicas Eletroquímicas/métodos , Poluentes Ambientais/análise , Indóis/química , Isoindóis , Microeletrodos
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