Removal of Ni (II) from aqueous solution by an electric arc furnace slag using artificial neural network approach

An artificial neural network (ANN) was built to model the adsorption of nickel on electric arc furnace slag (EAFS). The effect of operating parameters such as pH, the initial metal ion concentration, particle size, and adsorbent dosage were investigated to optimize the sorption process. The operating variables were used as the input for a neural network, which predicted the nickel (II) ion uptake at any time point as the output. The adsorbent was characterized by SEM and BET measurements. From the experimental results the adsorption capacity of 45% was obtained at pH of 8, also as when the adsorbent dosage increases from 0.1 to 1 g/l there is an increase in the percentage removal of Ni(II) ion from 25% to 37% respectively. Further more from the particle size analysis result, it revealed that as the particle size increases from 0.5µm to 3mm the percentage removal of Ni(II) ion decrease from 52% to 33%. Finally by increasing the initial concentration of Ni(II) ion from 50 to 1000 mg L-1, the adsorption capacity also increase from 24% to 43%. The ANN models present high correlation coefficient (R²=1) was found to perform excellently in predicting the adsorption behaviour of nickel in aqueous solutions onto EAFS

Grafting Carbon Nanotubes on Glass Fiber by Dip Coating Technique to Enhance Tensile and Interfacial Shear Strength

The effects of noncovalent bonding and mechanical interlocking of carbon nanotubes (CNT) coating on tensile and interfacial strength of glass fiber were investigated. CNT were coated over glass fiber by a simple dip coating method. Acid treated CNT were suspended in isopropanol solution containing Nafion as binding agent. To achieve uniform distribution of CNT over the glass fiber, an optimized dispersion process was developed by two parameters: CNT concentration and soaking time. CNT concentration was varied from 0.4 to 2 mg/mL and soaking time was varied from 1 to 180 min. The provided micrographs demonstrated appropriate coating of CNT on glass fiber by use of CNT-Nafion mixture. The effects of CNT concentration and soaking time on coating layer were studied by performing single fiber tensile test and pull-out test. The obtained results showed that the optimum CNT concentration and soaking time were 1 mg/mL and 60 min, respectively, which led to significant improvement of tensile strength and interfacial shear stress. It was found that, at other concentrations and soaking times, CNT agglomeration or acutely curly tubes appeared over the fiber surface which caused a reduction of nanotubes interaction on the glass fiber

The in vitro therapeutic activity of ellagic acid-alginate-silver nanopeprintss on breast cancer cells (MCF-7) and normal fibroblast cells (3T3)

The present work involves the development of EA-Alg-AgNPs nanocomposite based on ellagic acid (EA) as active compound. Silver nitrate was taken as the metal precursor (AgNPs) and sodium alginate (Alg) as a reducing agent. The EA-Alg-AgNPs nanocomposite was characterized using transmission electron microscopy (TEM), zeta potential, and in vitro release kinetics. The particles thus obtained were spherical in shape and having an average particles size of 10 nm, zeta potentials of –8.2 mV, and the release kinetics of EA from nanocomposite was following Hixson-Crowell kinetics models with R 2 = 0.9956. The cytotoxicity potential of free EA, Alg-AgNPs and the EA-Alg-AgNPs nanocomposite may be determined using a normal mouse fibroblast cells (3T3) and breast cancer cells (MCF-7). EA-Alg-AgNPs nanocomposite demonstrated a increased cytotoxicity effect when compared to free EA on MCF-7 cells with 15.3% cell viability at 128 μg/mL; compared to 33.5% cell viability in a direct EA exposure. It is worth mentioning the cytotoxicity of Alg-AgNPs against MCF-7 shows 28% viability at 128 μg/mL

Synthesis and characterization of silver nanoparticles mediated in glutathione and sodium alginate

Synthesis of silver nanoparticles (Ag NPs) has attracted huge interest from scientists due to its wide applications. Different pathways, such as physical and chemical reduction has been employed regarding the synthesis of Ag NPs. Many of them contain highly reactive chemicals and can cause potential environmental and biological risks. In comparison to those methods, green synthesis of nanoparticles using biopolymer provides a safe way of nanoparticle production with the size and shape of our interest. Nanoparticles formation depends on various factors such as metal ion concentration, pH, time and temperature as well as nature of reducing and stabilizing agent. There is a lack of a comprehensive study in optimizing important parameters for the green synthesis of Ag NPs in the biopolymer substrates. In this study, silver nanoparticles with the small size of 1 to 30 nm were successfully synthesized by green method in the substrate of sodium alginate (Na-Alg) and glutathione (GSH). Specific percentage of AgNO3 and biopolymeric substance were mixed together and stirred for different time at various temperature. Moreover, rapid synthesis of Ag NPs was achieved using an environmental friendly and biodegradable solvent that act as, stabilizing and reducing agent without use of high pressure or temperature, with the help of the accelerator. The silver nitrate, sodium alginate/glutathione, and sodium hydroxide were used as the silver precursor,stabilizer/ reducing agent and accelerator respectively. The crystalline structure of Ag NPs for all of the samples, the average size and size distributions, surface Plasmon resonance (SPR), surface morphology, and functional groups were studied using X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-visible spectroscopy (UV-vis), scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) respectively. The XRD analysis confirmed that the crystallographic planes of the silver crystals were the face-centered cubic (fcc) types. The UV-visible absorption spectra showed the peaks characteristic of the surface plasmon resonance (SPR) bands of Ag NPs. The antibacterial activities of Ag NPs were investigated against Gram-negative and Gram-positive bacteria by the disk diffusion method using Mueller-Hinton Agar (MHA) that show highly antibacterial activity of Ag NPs. The properties of Ag/Na-Alg and Ag/GSH were studied as the function of time,temperature, concentration and pH until a relatively stable size and size distribution were achieved. The results from the UV-visible spectroscopy and TEM demonstrated that the initial concentration of 0.1 M for AgNO3 ,1.5 wt% for Na-Alg and GSH, in 90°C after 12h stirring time of reaction are the optimum for the synthesis of Ag Nps incorporate in Na-Alg and GSH. In addition, 5 ml is the optimum amount of sodium hydroxide (NaOH) for synthesis of Ag Nps in short time (30 minutes) of the reaction. From the results, all objective was achieved

Rapid and green synthesis of silver nanoparticles via sodium alginate media

This study focuses on influence of accelerator in rapidly and green synthesis of silver nanoparticles (Ag-NPs) with the natural polymeric matrix. Silver nitrate, sodium alginate (Na-Alg) and sodium hydroxide have been used as silver precursor, stabilizer/reducing agent, and accelerator reagent, respectively. The resulting products have been confirmed to be Ag-NPs smaller than 20 nm using powder X-ray diffraction (PXRD), UV-visible spectroscopy (UV-vis), Fourier transform infrared (FT-IR) spectroscopy as well as transmission electron microscopy (TEM) and scanning electron microscopy. The colloidal solutions of Ag-NPs obtained at different volumes of NaOH show strong and different surface plasmon resonance (SPR) peaks, which can be explained from the TEM images of Ag-NPs and their particle size distribution. Compared with other synthetic methods, this work is rapid, green and simple to use. The newly prepared Ag-NPs may have many potential applications in chemical pharmaceutical and food industries

Rapid and green synthesis of silver nanoparticles via sodium alginate media

This study focuses on influence of accelerator in rapidly and green synthesis of silver nanoparticles (Ag-NPs) with the natural polymeric matrix. Silver nitrate, sodium alginate (Na-Alg) and sodium hydroxide have been used as silver precursor, stabilizer/reducing agent, and accelerator reagent, respectively. The resulting products have been confirmed to be Ag-NPs smaller than 20 nm using powder X-ray diffraction (PXRD), UV-visible spectroscopy (UV-vis), Fourier transform infrared (FT-IR) spectroscopy as well as transmission electron microscopy (TEM) and scanning electron microscopy. The colloidal solutions of Ag-NPs obtained at different volumes of NaOH show strong and different surface plasmon resonance (SPR) peaks, which can be explained from the TEM images of Ag-NPs and their particle size distribution. Compared with other synthetic methods, this work is rapid, green and simple to use. The newly prepared Ag-NPs may have many potential applications in chemical pharmaceutical and food industries

Stirring time effect of silver nanoparticles prepared in glutathione mediated by green methods

Background: This study aims to investigate the influence of different stirring time for synthesis of silver nanoparticles in glutathione (GSH) aqueous solution. The silver nanoparticles (Ag-NPs) were prepared by green synthesis method using GSH as reducing agent and stabilizer, under moderate temperature at different stirring times. Silver nitrate (AgNO3) was taken as the metal precursor while Ag-NPs were prepared in the over reaction time. Results: Formation of Ag-NPs was determined by UV–vis spectroscopy where surface plasmon absorption maxima can be observed at 344–354 nm from the UV–vis spectrum. The synthesized nanoparticles were also characterized by X-ray diffraction (XRD). The peaks in the XRD pattern confirmed that the Ag-NPs possessed a face-centered cubic and peaks of contaminated crystalline phases were unable to be located. Transmission electron microscopy (TEM) revealed that Ag-NPs synthesized were in spherical shape. Zeta potential results indicate that the stability of the Ag-NPs is increases at the 72 h stirring time of reaction comparison to GSH. The Fourier transform infrared (FT-IR) spectrum suggested the complexation present between GSH and Ag-NPs. The use of green chemistry reagents, such as peptide, provides green and economic features to this work. Conclusions: Ag-NPs were successfully synthesized in GSH aqueous solution under moderate temperature at different stirring times. The study clearly showed that the Ag-NPs synthesized in the long times of stirring, thus, the kinetic of GSH reaction is very slow. TEM results shows that with the increase of stirring times the mean particle size of Ag-NPs become increases. The FT-IR spectrum suggested the complexation present between GSH and Ag-NPs. These suggest that Ag-NPs can be employed as an effective bacteria inhibitor and can be applied in medical field

ORIGINAL ARTICLE Corresponding Author Removal of Ni (II) from aqueous solution by an electric arc furnace slag using artificial neural network approach

; Removal of Ni (II) from aqueous solution by an electric arc furnace slag using artificial neural network approach ABSTRACT An artificial neural network (ANN) was built to model the adsorption of nickel on electric arc furnace slag (EAFS). The effect of operating parameters such as pH, the initial metal ion concentration, particle size, and adsorbent dosage were investigated to optimize the sorption process. The operating variables were used as the input for a neural network, which predicted the nickel (II) ion uptake at any time point as the output. The adsorbent was characterized by SEM and BET measurements. From the experimental results the adsorption capacity of 45% was obtained at pH of 8, also as when the adsorbent dosage increases from 0.1 to 1 g/l there is an increase in the percentage removal of Ni(II) ion from 25% to 37% respectively. Further more from the particle size analysis result, it revealed that as the particle size increases from 0.5µm to 3mm the percentage removal of Ni(II) ion decrease from 52% to 33%. Finally by increasing the initial concentration of Ni(II) ion from 50 to 1000 mg L -1 , the adsorption capacity also increase from 24% to 43%. The ANN models present high correlation coefficient (R 2 =1) was found to perform excellently in predicting the adsorption behaviour of nickel in aqueous solutions onto EAFS

Biosorption of azoimide on almond integument: Kinetics, isotherm and thermodynamics studies

Hospital effluents are a serious problem in waterways due to azoimide that provides physical and health hazards. The removal of azoimide using powdered almond integument was studied in batch mode. Hydroxyl, carbonyl and carboxyl on the biosorbent surface were measured by titration method. The biosorption of azoimide was found to depend on the initial concentrations, pH and contact time. The equilibrium data was analyzed by using a non-linear form of Langmuir, Freundlich, Toth and Redlich-Peterson isotherm models. The fitness of data was evaluated using three error functions and correlation coefficient value (R 2). The error analysis showed three parameters models described the best biosorption in comparison of two parameters models such as Langmuir and Freundlich. The pseudo-first order, pseudo-second order and Elovich kinetic models were applied to study the kinetic behavior, and revealed applicability of the pseudo-second order model. The evaluation of thermodynamic parameters showed that biosorption process was endothermic and spontaneous. © 2013 Elsevier Ltd. All rights reserved.info:eu-repo/semantics/publishe