18 research outputs found

    Pseudo-stem banana fiber as a potential low-cost adsorbent to remove methylene blue from synthetic wastewater

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    In this work, pseudo-stem banana (Musa acuminata) (PBF) fiber was utilized as a potential low-cost natural adsorbent to uptake methylene blue (MB) dye from synthetic wastewater by batch adsorption process. Different adsorption factors like contact time, pH, initial concentration, and adsorbent dosage were explored and found that the separation process is strongly pH dependent. Additionally, the adsorption data were fitted with various adsorption isotherms like Langmuir, Freundlich, Temkin, and Dubinin-Radhushkevich models to detect the adsorption equilibrium phenomena. Reaction kinetics was inspected using pseudo-first-order and second-order kinetic models. Mass transfer and intra-particle diffusion analyses indicate the adsorption mechanism of the system described particularly in the context. Furthermore, scanning electron spectroscopy (SEM) and Fourier transformed infrared spectroscopy (FTIR) were conducted to get the morphology and surface properties of the adsorbent, respectively. As a result, the as-prepared banana fiber can be proposed as a cheap suitable adsorbent to separate dyestuffs from industrial wastewater.Peer reviewe

    Preparation of magnesium diniobate by solid-state reactions and its role for hydrogen storage

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    A ternary compound of magnesium diniobate (MgNb2O6) was prepared by solid–state reactions in order to understand the role of transition metal oxides as a promoter/catalyst for hydrogen storage in Mg/MgH2 systems. MgNb2O6 was prepared in almost pure form in oxidizing conditions by annealing a stoichiometric mixture of MgO and Nb2O5. The effect of calcination temperatures on phase formation, reaction kinetics, and heat of reaction of the solid–state product was investigated by ex situ, in situ X-ray diffraction (XRD), and differential scanning calorimetry (DSC). Hydrogen sorption properties of the compound were investigated by mass spectrometer. The crystallographic parameters of binary and ternary Mg–Nb–O phases were extracted by Rietveld method. During solid–state synthesis, the formation of MgNb2O6 provides single-step reaction between precursor materials proved by in situ experiment and the heat of formation as well as driving force was calculated from calorimetric analysis

    Effect of Manganese on Radiation Vulcanization of Natural Rubber

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    Manganese was added as a promoter to investigate physico-mechanical properties of radiation-vulcanized natural rubber latex (RVNRL) films. RVNRL films were prepared by the addition of Mn with the concentration range 0–30 ppm to natural rubber latex and irradiated with various radiation doses (0–20 kGy). Tensile strength, tear strength, and cross-linking density of the irradiated rubber films increased with increasing the concentration of Mn ions as well as radiation doses. In contrast, elongation at break, permanent set, and swelling ratio of the films were decreased under the same conditions. The concentration of Mn ions and radiation doses were optimized and found to be 20 ppm and 12 kGy, respectively. The maximum tensile and tear strengths of irradiated rubber films were observed as 29.12 MPa and 44.78 N/mm, respectively at the optimum conditions. The mechanical properties of the films increased markedly with the addition of Mn until they attained the highest values of 33.88 MPa and 54.77 N/mm, respectively. These enhancements, which reached approximately 20% at the most favorable conditions, can be explained by the effect of transition metals in view of Fajan’s rules regarding the covalent character of ionic bonds and suggest that the higher the difference in charges between cation and anion, the higher the ability to form distortion or polarization of ions

    Investigation of Polymer Degradation by Adding Magnesium

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    The effect of alkali metal magnesium on polymer degradation of physico-mechanical properties of radiation-vulcanized natural rubber latex (RVNRL) films was investigated. RVNRL films were prepared by the addition of Mg of different concentrations (0–30 ppm) to natural rubber latex and irradiation with various radiation doses (0–20 kGy). The radiation doses were optimized (12 kGy), and the adverse effect of Mg was studied against a reference film prepared without metal. Tensile strength, tear strength, and cross-linking density of the irradiated rubber films were decreased with increasing metal ion concentrations and decreasing radiation doses. The mechanical properties of the films were reduced by nearly 10% for 30 ppm Mg ions and at the optimum dose. In contrast, elongation at break, permanent set, and swelling ratio of the films were increased at the same conditions. The maximum tensile and tear strengths of irradiated rubber films without additive were 29.33 MPa and 47.95 N/mm, respectively, at a radiation dose of 12 kGy, and these values were about six times higher than those of blank samples. With the addition of Mg, the corresponding values decrease continuously, and the minimum values were found to be 26.35 MPa and 42.675 N/mm, respectively. The effect of divalent alkali metal on polymer chain scission can be explained by the classical electron concept reported in this article

    A proposed kinetic model for hydrogen sorption in MgH 2

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    Gamma-Irradiated Gelatin-Based Films Modified by HEMA for Medical Application

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    The present article describes the synthesis and characterization of bi-component polymer systems based on gelatin films incorporated with 2-hydroxyethyl methacrylate (HEMA) monomer, developed for medical application. Gelatin films were prepared by the addition of HEMA of different concentrations (0–30 wt.%) and irradiated with various radiation doses (0–5 kGy). Tensile strength and tear strength of the irradiated gelatin films were found to increase with increasing HEMA up to 20 wt.% as well as radiation doses (1 kGy) as optimized. The maximum tensile and tear strengths of irradiated gelatin films with HEMA were found to be 79.1 MPa and 83.2 N/mm, respectively, at the optimum conditions, and these values were about double that of a reference film prepared without additives. In addition, morphological analysis was done by scanning electron microscopy (SEM) and showed how HEMA cemented and was covered with gelatin in the blend. Thermomechanical analysis was carried out to investigate the shifting of glass transition temperature (Tg) towards higher temperature due to HEMA addition, and the effect of this film was tested on the human body in order to determine whether it can be applied for medical purposes

    Tea Dust as a Potential Low-Cost Adsorbent for the Removal of Crystal Violet from Aqueous Solution

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    The present work demonstrates tea dust (TD) as a potential low-cost adsorbent for the removal of crystal violet (CV) from aqueous solution by batch adsorption technique. Reaction kinetics and isotherm studies were carried out under various conditions of initial dye concentration, contact time, adsorbent dosage, and pH. The adsorbent was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR) and Brunauer–Emmett–Teller. FTIR results showed complexation and ion exchange appeared to be the principle mechanism for CV adsorption. The adsorption isotherm data were fitted to Langmuir and Freundlich equations; and the maximum adsorption capacity was found to be 175.4 mg/g. The removal of CV by TD followed the unified approach model. Therefore, TD can be employed as an efficient and cost-effective adsorbent in industrial wastewater treatment for the removal of basic dyes

    Tailoring Base Catalyzed Synthesis of Palm Oil Based Alkyd Resin Through CuO Nanoparticles

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    Palm oil based alkyd resin was synthesized by an alcoholysis–polyesterification process over a base catalyst tailored by copper oxide (CuO) nanoparticles. In the present paper we synthesized CuO sol in glycerol and subsequently used it in alkyd resin synthesis. The formation of the alkyd resin was confirmed by FTIR, Raman, 1H-NMR and 13C-NMR methods and its molecular weight was determined by gel permeation chromatography (GPC). The antimicrobial activity of the pseudo-homogeneous additive was determined via the Kirby–Bauer method and the stability of the CuO was determined by X-ray absorption near edge structure spectroscopy (XANES). The addition of CuO nano-sol to the conventional homogeneous base catalyzed system explored a new catalytic route for the preparation of bioresin from vegetable oil, reducing the reaction time as well as adding antimicrobial properties to the resin

    Glycerolysis of Palm Oil Using Copper Oxide Nanoparticles Combined With Homogeneous Base Catalyst

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    In the present work, a new catalyst system composed of copper oxide nanoparticles (CuO-nano) along with a conventional homogeneous base catalyst (NaOH) for the glycerolysis of palm oil to produce monoglycerides (MG) was proposed. CuO-nano was synthesized in glycerol and directly used in the glycerolysis reactions, which formed a pseudo-homogeneous system. The production of MG and diglycerides (DG) from oil was monitored by using 1H-NMR, 13C-NMR and HPLC. When compared with the conventional NaOH catalyst, CuO-nano used alone showed less activity, but adding NaOH to the CuO-nano exhibited a synergistic effect by increasing the MG yield significantly. The oil conversion, MG and DG yield were achieved at 95, 71 and 24%, respectively, for the new catalyst system composed of CuO-nano and NaOH. The mechanism of the glycerolysis reaction over CuO-nano and NaOH was elucidated

    Removal of Dark Blue-GL from Wastewater using Water Hyacinth: A Study of Equilibrium Adsorption Isotherm

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    The present investigation demonstrates that water hyacinth root is a potential adsorbent for the removal of dark blue-GL dye from wastewater by batch process. Various operating parameters such as the adsorption capacity, initial dye concentration, contact time, effect of pH, and adsorbent dosage were examined at different experimental conditions. The effect of pH and dye concentration found to be crucial, have been optimized, and the maximum recovery (~90%) was detected at pH 3 and concentration 150 ppm. The separation of dark blue-GL is proportionally related to the adsorbent dosage, and up to 77% dye was recovered for the dose 1.5 g/L. Langmuir adsorption isotherm model of the adsorption process was carried out at the equilibrium concentration of dark blue-GL uptake, and the corresponding data were analyzed by the least square methods. Kinetic parameters calculated from the tentative data could be fitted well to a pseudo-second-order kinetic model. These results point out aptness of the adsorbent in the niche area due to high adsorption capacity (~24 g/kg) and can be applied in the execution of dark blue-GL-enriche
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