26 research outputs found

    Enhanced solar light photocatalytic performance of Fe-ZnO in the presence of H2O2, S2O82−, and HSO5− for degradation of chlorpyrifos from agricultural wastes: Toxicities investigation

    Get PDF
    This study reported Fe doped zinc oxide (Fe-ZnO) synthesis to degrade chlorpyrifos (CPY), a highly toxic organophosphate pesticide and important sources of agricultural wastes. Fourier transform infrared, X-ray diffraction, scanning electron microscope, and energy-dispersive X-ray spectroscopic analyses showed successful formation of the Fe-ZnO with highly crystalline and amorphous nature. Water collected from agricultural wastes were treated with Fe-ZnO and the results showed 67% degradation of CPY by Fe-ZnO versus 39% by ZnO at 140 min treatment time. Detail mechanism involving reactive oxygen species production from solar light activated Fe-ZnO and their role in degradation of CPY was assessed. Use of H2O2, peroxydisulfate (S2O82−) and peroxymonosulfate (HSO5−) with Fe-ZnO under solar irradiation promoted removal of CPY. The peroxides yielded hydroxyl ([rad]OH) and sulfate radical ([Formula presented]) under solar irradiation mediated by Fe-ZnO. Effects of several parameters including concentration of pollutant and oxidants, pH, co-existing ions, and presence of natural organic matter on CPY degradation were studied. Among peroxides, HSO5− revealed to provide better performance. The prepared Fe-ZnO showed high reusability and greater mineralization of CPY. The GC-MS analysis showed degradation of CPY resulted into several transformation products (TPs). Toxicity analysis of CPY as well as its TPs was performed and the formation of non-toxic acetate imply greater capability of the treatment technology

    Simultaneous determination of monosaccharides and oligosaccharides in dates using liquid chromatography-electrospray ionization mass spectrometry

    Get PDF
    a b s t r a c t Ultra performance liquid chromatography coupled to mass spectrometry was used for the simultaneous separation and determination of reducing monosaccharides (fructose and glucose), a non-reducing disaccharide (sucrose) and oligosaccharides (kestose and nystose) in HILIC mode. The chromatographic separation of all saccharides was performed on a BEH amide column using an acetonitrile-water gradient elution. The detection was carried out using selected ion recording (SIR) acquisition mode. The validation of the proposed method showed that the limit of detection and limit of quantification values for the five analyzed compounds were in the range of 0.25-0.69 lg/mL and 0.82-3.58 lg/mL, respectively; while the response was linear in the range of 1-50 lg/mL. The developed method showed potential usefulness for a rapid and sensitive analysis of underivatized saccharides and was used for determination of sugars in three date samples (Sefri, Mabroom, Ghassab) which were soxhlet extracted by ethanol

    A Green Approach for the Synthesis of Silver Nanoparticle-Embedded Chitosan Bionanocomposite as a Potential Device for the Sustained Release of the Itraconazole Drug and Its Antibacterial Characteristics

    No full text
    The present research work intended to demonstrate the green synthesis of silver nanoparticles (AgNPs) using the plant extract Saccharum officinarum, and then the development of chitosan–silver (CH-Ag) bionanocomposite. The synthesized AgNPs were characterized using UV spectroscopy, Fourier transform infrared (FTIR), and transmission electron microscopy (TEM). The maximum absorption spectrum peak was observed at 420 nm, revealing the formation of AgNPs by the stem extract of S. officinarum. The AgNPs sizes were in the range of 10–50 nm. Itraconazole is an antifungal that is used as a novel drug to study its release through synthesized bionanocomposite. Different kinetic models, such as zero order, first order, Korsmeyer–Peppas, Hixson–Crowell and Higuchi, were used to study the drug release profile from the synthesized CH-Ag bionanocomposite. The first-order kinetic model showed the best fit for the drug release with the maximum regression coefficient value. The antibacterial activity of the synthesized CH-Ag bionanocomposite was examined against Bacillus cereus, Staphylococcus, and Escherichia coli, and it was shown to be efficient against these strains

    Investigation the Effects of Green-Synthesized Copper Nanoparticles on the Performance of Activated Carbon-Chitosan-Alginate for the Removal of Cr(VI) from Aqueous Solution

    No full text
    In the present investigation, green nano-zerovalent copper (GnZVCu), activated carbon (AC), chitosan (CS) and alginate (ALG) nanocomposites were produced and used for the elimination of chromium (VI) from a polluted solution. The nanocomposites GnZVCu/AC-CS-alginate and AC-CS-alginate were prepared. Analysis and characterization were performed by the following techniques: X-ray diffraction, energy dispersive X-ray spectroscopy, scanning electron microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. The SEM analysis revealed that the nanocomposites are extremely mesoporous, which leads to the greatest adsorption of Cr+6 (i.e., 97.5% and 95%) for GnZVCu/AC-CS-alginate and AC-CS-alginate, respectively. The adsorption efficiency was enhanced by coupling GnZVCu with AC-CS-alginate with a contact time of 40 min. The maximum elimination of Cr+6 with the two nanocomposites was achieved at pH 2. The isotherm model, Freundlich adsorption isotherm and kinetics model and P.S.O.R kinetic models were discovered to be better suited to describe the exclusion of Cr+6 by the nanocomposites. The results suggested that the synthesized nanocomposites are promising for the segregation of Cr+6 from polluted solutions, specially the GnZVCu/AC-CS-alginate nanocomposite

    Internet of things with nanomaterials-based predictive model for wastewater treatment using stacked sparse denoising auto-encoder

    No full text
    Wastewater is a serious concern for the environment. There is a substantial amount of toxins that are discharged continuously from several pharmacological companies that lead to serious damage to public health and the ecosystem. Present wastewater treatment technologies include primary, tertiary, and secondary treatments that remove numerous contaminants; but pollutants in the nanoscale range were hard to remove with these steps. Some of these include inorganic and organic pollutants, pathogens, pharmaceuticals, and pollutants of developing concern. The utility of nanoparticles was a promising solution to this issue. Nanoparticles have exclusive properties permitting them to potentially eliminate residual pollutants but being eco-friendly and inexpensive. This study develops a new Archimedes optimization algorithm (AOA) with Stacked Sparse Denoising Auto-Encoder (SSDAE) model, named AOA-SSDAE for wastewater management in the IoT environment. The presented AOA-SSDAE technique aims to predict wastewater treatment depending on the influent indicators. In the presented AOA-SSDAE technique, the IoT devices are initially employed for the data collection process and then data normalization is performed to transform the collected data into a uniform format. For the predictive process, the SSDAE model is employed in this paper. To improve the SSDAE model's prediction capability, the AOA-based hyperparameter tuning process is involved. HIGHLIGHT AOA-SSDAE is a novel Archimedes optimization algorithm (AOA) model with Stacked Sparse Denoising Auto-Encoder (SSDAE) for wastewater management in the context of the Internet of Things (IoT).; The AOA-SSDAE method presented here aims to forecast wastewater treatment based on indicators of the influent.; In the provided AOA-SSDAE methodology, IoT devices are initially used for data collection, followed by data normalization to convert the collected data into a standard format.

    Fabrication and characterization of xanthan gum-cl-poly(acrylamide-co-alginic acid) hydrogel for adsorption of cadmium ions from aqueous medium

    Get PDF
    This article belongs to the Special Issue Advance in Composite GelsThe present research demonstrates the facile fabrication of xanthan gum-cl-poly(acrylamide-co-alginic acid) (XG-cl-poly(AAm-co-AA)) hydrogel by employing microwave-assisted copolymerization. Simultaneous copolymerization of acrylamide (AAm) and alginic acid (AA) onto xanthan gum (XG) was carried out. Different samples were fabricated by changing the concentrations of AAm and AA. A sample with maximum swelling percentage was chosen for adsorption experiments. The structural and functional characteristics of synthesized hydrogel were elucidated using diverse characterization tools. Adsorption performance of XG-cl-poly(AAm-co-AA) hydrogel was investigated for the removal of noxious cadmium (Cd(II)) ions using batch adsorption from the aqueous system, various reaction parameters optimized include pH, contact time, temperature, and concentration of Cd(II) ions and temperature. The maximum adsorption was achieved at optimal pH 7, contact time 180 min, temperature 35 °C and cadmium ion centration of 10 mg·L-1. The XG-cl-poly(AAm-co-AA) hydrogel unveiled a very high adsorption potential, and its adsorption capacities considered based on the Langmuir isotherm for Cd(II) ions was 125 mg·g-1 at 35 °C. The Cd(II) ions adsorption data fitted nicely to the Freundlich isotherm and pseudo-first-order model. The reusability investigation demonstrated that hydrogel retained its adsorption capacity even after several uses without significant loss.The authors acknowledge the Researchers Supporting Project number (RSP-2021/8), King Saud University, Riyadh, Saudi Arabia for the financial support

    Metal Organic Framework-Based Dispersive Solid-Phase Microextraction of Carbaryl from Food and Water Prior to Detection by Ultra-Performance Liquid Chromatography-Tandem Mass Spectrometry

    No full text
    In this work, metal organic frameworks (A100 Al-based MOFs) were used in dispersive solid-phase microextraction (DSPME) for the isolation and preconcentration of the carbaryl from vegetable, fruit and water samples. The A100 Al-based MOFs showed excellent behavior for the adsorption of carbaryl from a water-ethanol solution; additionally, carbaryl was easily desorbed with ethyl acetate for detection by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-TMS). The analytical process of DSPME together with UPLC-TMS provides the accurate monitoring of trace carbaryl residues. The results show that the optimal recovery% of carbaryl was obtained at a sample apparent pH of 5, with the application of 1 mL of ethyl acetate to elute the carbaryl from the A100 Al-based MOFs. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.01 mg.L-1 and 0.03 mg.L-1, respectively. The RSD% was 0.8-1.9, and the preconcentration factor was 45. DSPME and UPLC-TMS were successfully used for the isolation and detection of carbaryl in food and water samples

    Naturally Occurring Montmorillonite-Based Polymer Monolith Composites as Stationary Phases for Capillary Liquid and Gas Chromatography

    No full text
    This work is associated with the preparation of capillary chromatographic columns containing inorganic-organic composites comprised of naturally occurring montmorillonite (MMT) clay mineral and polymethacrylate monolithic material. The prepared composites combine the best qualities of both constituents, offering desirable properties for use under the disparate conditions of both GC and HPLC at the same time. The stationary phases were investigated by scanning electron microscopy (SEM), the specific surface area, and thermogravimetric analysis (TGA) and examined in terms of various conditions utilized for GC and HPLC methods. The prepared columns demonstrated an excellent permeability and stability against common chromatographic conditions, such as the eluent type, flow rate, pressure, and temperature. The results confirmed that the addition of small amounts of MMT into the monolith induced significant improvement in the specific surface area, which contributed to the formation of more active sites and enhanced the retention of analytes. The registered column backpressures did not exceed 980 kPa and 16,500 kPa for the prepared GC and HPLC columns, respectively. The prepared columns were subjected to the separation of various interesting compounds possessing different chemistries and polarities, including alkanes, alkylbenzenes, polycyclic aromatic hydrocarbons (PAHs), alcohols, ketones, phenols, some common organic solvents, and isomeric mixtures. Under the optimal conditions, the efficiency of the columns fell between 4900–38,500 plates m−1 for GC and 3400–58,800 plates m−1 for capillary HPLC applications. In all cases, the measured chromatographic resolution was more than 1.38, with excellent an peak symmetry and low tailing factors. In comparison with the most commonly used commercial columns, the polysiloxane open tubular column for GC and silica-based C18 packed column for HPLC, the prepared GC columns demonstrated a faster separation with a higher efficiency, comparable resolution and tailing factors, and lower consumption of carrier gas. Regarding the capillary columns prepared for HPLC, the chromatographic experiments exposed a much lower run time with a comparable efficiency and resolution and drastically lower consumption of mobile phase solvents and samples. The results demonstrate that the MMT-based polymethacrylate monolith composites are applicable as novel and promising separation media for analyzing various mixtures of interest in different fields, such as petrochemical and environmental samples

    Supramolecular solvent microextraction and ultra-performance liquid chromatography-tandem mass spectrometry combination for the preconcentration and determination of malathion in environmental samples

    No full text
    A supramolecular solvent microextraction method was used for the fast and selective preconcentration separation of malathion, and then ultra-performance liquid chromatography-tandem mass spectrometry was applied for the detection of malathion. The supramolecular solvent is a suitable medium for malathion collection from the sample extract. The results showed that the quantitative recovery of malathion was obtained at pH 4 with heptanol-tetrahydrofuran as the supramolecular solvent. The preconcentration of malathion by the developed microextraction method was established within 10 min. The limit of detection and the quantification limit were 1.4 and 4.2 mu g/L, respectively. A preconcentration factor of 40 was obtained, and the relative standard deviation was <7%. The developed supramolecular solvent microextraction method was applied for different real samples, including fruits, vegetables, and water samples
    corecore