scholarly journals Radiation-induced Grafting of Styrene onto Polyethylene Films for Preparation of Cation Exchange Membranes: Effect of Crosslinking+

2017 ◽  
Vol 2 (1) ◽  
Author(s):  
M. M. Nasef ◽  
H. Saidi ◽  
A. H. Yahaya
Keyword(s):  
Cation Exchange ◽  
Chemical Properties ◽  
Exchange Capacity ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Swelling Properties ◽  
Ion Exchange Capacity ◽  
Physico Chemical ◽  
Styrene Divinylbenzene ◽  
Radiation Induced

Crosslinked cation exchange membranes bearing sulfonic acid groups (PE-g-PSSA/DVB) were prepared by radiationinduced grafting of styrene/divinylbenzene (DVB) mixtures onto low density polyethylene (PE) films followed by sulfonation reactions. The effect of addition of DVB (2 and 4%) on the grafting behavior and the physico-chemical properties of the membranes such as ion exchange capacity, swelling and ionic conductivity were evaluated incorrelation with grafting yield (Y%). The structural and thermal properties of the membranes were also studied using differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA), respectively. Crosslinking with DVB was found to considerably affect the properties of the membranes in a way that reduces the swelling properties and enhances the chemical stability. The ion conductivity of the crosslinked membranes recorded a level of 10–2 S/cm at sufficient grafting yield (28%) despite the reduction caused by the formation of crosslinking structure. The results of this work suggest that membranes prepared in this study are potential alternatives for various electrochemical applications.

Surface decontamination in fuel manufacture plants by chelating solution of nanoparticles

2017 ◽  
Vol 0 (0) ◽  
Author(s):  
T. M. Morsi ◽  
Ahmed M. Elbarbary ◽  
Mohamed M. Ghobashy ◽  
Sameh H. Othman
Keyword(s):  
Cyano Group ◽  
Chemical Properties ◽  
Germanium Detector ◽  
Gravimetric Analysis ◽  
Uniform Size ◽  
Transmission Electron ◽  
Physico Chemical ◽  
Radiation Induced ◽  
Surface Decontamination ◽  
Thermal Stability Of

AbstractA nanoparticles chelating solution was synthesized by copolymerization of acrylonitrile (AN) and methacrylic acid (MAA) by radiation induced polymerization technique using 17 kGy irradiation doses. A high copolymer yield was obtained by using 80/20% of AN/MAA and comonomer concentration of 50% (w/w) at a dose rate of 2.58 KGy/h. The resultant cyano group (–CN) of nano-poly(AN/MAA) was converted by chemical modification using hydroxylamine (NH2–OH) to an amidoxime group [–C(=NOH)NH2], which was then confirmed by Fourier transform infrared spectroscopy (FTIR). The physico-chemical properties of poly(AN/MAA) and amidoximated poly(AN/MAA) nanoparticles were studied by FTIR, transmission electron microscopy (TEM), dynamic light scattering (DLS) and thermal gravimetric analysis (TGA). The morphological analysis by TEM and DLS showed a spherical and uniform size of the amidoximated poly(AN/MAA) nanoparticles. TGA results indicated that the thermal stability of poly(AN/MAA) increased by the amidoximation process. The surface decontamination due to uranium was also investigated by the prepared chelating nanoparticles solution. A high purity germanium detector (HPGe) was used as a surface contamination detection tool. The results showed the presence of peaks at different energies, namely, 186.2 keV for Ra-226 (U-238) and 143.76 keV, 163.35 keV and 205.31 for U-235 before the decontamination process. The disappearance of these peaks after decontamination confirmed the applicability and efficiency of the nanoparticles solution in uranium surface decontamination.

scholarly journals Physico-chemical Properties of Soil of Rangapani Tea Estate of Bangladesh

2011 ◽  
Vol 3 (3) ◽  
pp. 683-688
Author(s):  
M. N. Islam ◽  
A. F. M. Sanaullah
Keyword(s):  
Cation Exchange ◽  
Cation Exchange Capacity ◽  
Chemical Properties ◽  
Clay Content ◽  
Exchange Capacity ◽  
Soil Samples ◽  
Physico Chemical ◽  
Different Depths ◽  
Chemical Properties Of Soils ◽  
Topographic Positions

Bangladesh is one of the tea producing countries of the world. It has 163 tea estates. Rangapani is a low yielding tea estate relative to other neighboring tea estates of Chittagong district in Bangladesh. A total 54 soil samples were collected from six different hills and three topographic positions having different depths of Rnagapanni Tea-Estate. Physico-Chemical properties of soils such as active acidity, reserve acidity, cation exchange capacity and clay content of the collected soil samples were determined. The measured parameters of the soil samples were plotted and analyzed with reference to site and topography. The parameters have been found to vary with sampling sites, depths and topography. Active acidity and reserve acidity were very low, with some exceptions compared to the optimum range for tea cultivation. Sand, silt, clay and cation exchange capacity (CEC) were found in reasonable range Keywords:  Soil; Active acidity; Reserve acidity; Cation exchange capacity; Clay content. © 2011 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved. doi: 10.3329/jsr.v3i3.7503               J. Sci. Res. 3 (3), 683-688 (2011)

scholarly journals Effect оf delamination оn physico-chemical properties of kaolin

2021 ◽  
Vol 53 (2) ◽  
pp. 253-266
Author(s):  
Slavica Mihajlovic ◽  
Milica Vlahovic ◽  
Nenad Vusovic ◽  
Natasa Djordjevic ◽  
Marina Jovanovic
Keyword(s):  
Crystal Structure ◽  
Particle Size ◽  
Cation Exchange ◽  
Friction Force ◽  
Layered Structure ◽  
Cation Exchange Capacity ◽  
Chemical Properties ◽  
Exchange Capacity ◽  
Physico Chemical ◽  
Plastic Processing

To provide the quality required for its use, raw kaolin must be subjected to certain processing procedures like delamination which is applied to the layered structure materials. The aim of this research is to determine the possibility of performing delamination in the extruder and to estimate the effects of this process on the physico-chemical properties of kaolin. The results showed that delamination can be efficiently realized in the extruder by shearing densely packed layers under the influence of friction force and added Na2CO3 electrolyte. The crystal structure of the system was thus disrupted. This was confirmed by the Hinckley index (HI) decrease and by the dilatometric characteristics changes during heating. The particle size was reduced and, furthermore, new adsorption centers were formed, which led to an increase in the total cation exchange capacity (CEC). The plasticity of kaolin decreased with the increasing delamination degree, as well as the amount of water required for plastic processing, which is favorable in drying ceramic products.

Synthesis, Characterization and Evaluation of Property Profile of Hybrid Ion- Exchanger

2013 ◽  
Vol 856 ◽  
pp. 64-68 ◽  
Author(s):  
Balbir Singh Kaith ◽  
Saruchi ◽  
Sandeep Kaur ◽  
Meenakshi Devi
Keyword(s):  
Ion Exchange ◽  
Chemical Properties ◽  
Reaction Medium ◽  
Monomer Concentration ◽  
Exchange Capacity ◽  
Ion Exchanger ◽  
Reaction Conditions ◽  
Ion Exchange Capacity ◽  
Physico Chemical ◽  
Different Temperatures

Gum tragancanthbased organic-inorganic hybrid ion exchanger has been synthesized using a mixture of sodium tungstate, orthophosphoric acid and potassium iodate. The different reaction conditions like reaction temperature, reaction time, pH of reaction medium, solvent volume, monomer concentration and initiator concentration were optimized in order to get the semi-IPN Gt-cl-poly (AA). Onto semi IPN, methylmethacrylate was incorporated using lipase-gluteraldehyde as the initiator-crosslinker system. The IPN finally was converted into ion-exchanger and was studied for its different physico-chemical properties. Ion exchange capacity was studied for Na+and effect of different temperatures on ion exchange capacity was evaluated. Characterization was done using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and EDS techniques.

scholarly journals Physicochemical Characterization of Biomass Residue–Derived Biochars in Vietnam

2018 ◽  
Author(s):  
Nguyen Van Hien ◽  
Eugenia Valsami-Jones ◽  
Nguyen Cong Vinh ◽  
Tong Thi Phu ◽  
Nguyen Thi Thanh Tam ◽  
...  
Keyword(s):  
Cation Exchange ◽  
Rice Husk ◽  
Cation Exchange Capacity ◽  
Physicochemical Characterization ◽  
Chemical Properties ◽  
Exchange Capacity ◽  
Bet Surface Area ◽  
Sem Images ◽  
Surface Areas ◽  
Physico Chemical

This study compares the physico-chemical characteristics of three different types of biochar produced from biomass residues in Vietnam as a basis for optimising their application in water purification and soil fertilisation.  Wood biochar (WBC), rice husk biochar (RBC), and bamboo biochar (BBC) were produced under limited oxygen conditions using equipment available locally in Vietnam, known as a Top-Lid Updraft Drum (TLUD). The resulting biochars were characterised using a suite of state-of-the-art methods to understand their morphology, surface chemistry and cation exchange capacity.  Surface areas (measured by BET) for WBC and BBC were 479.34 m2/g and 434.53 m2/g, respectively, significantly higher than that of RBC which was only 3.29 m2/g.  The morphology as shown in SEM images corresponds with the BET surface area, showing a smooth surface for RBC, a hollow surface for BBC, and a rough surface for WBC.  All three biochars produced alkaline, with pH values around 10, and all have high carbon contents (47.95 - 82.1 %).  Cation exchange capacity (CEC) was significantly different (p<0.05) among the biochars, being 26.70 cmol/kg for RBC, 20.7 cmol/kg for BBC, and 13.53 cmol/kg for WBC, which relates to the cations (Ca, Mg, K) and functional groups with negative charge (carboxyl, hydroxyl) present on the biochar surfaces.  The highest contents of Ca, Mg and K in rice husk BC may explain its highest CEC values.  Thus, although the biochars were produced by the same method, the various feedstocks lead to quite different physico-chemical properties.  Ongoing work is linking these physico-chemical properties to the biochar efficiencies in terms of nitrate and ammonia capture capacities for use as fertilisers, and for adsorption of heavy metals (Zn, Cu) or water filtration, in order to design optimal biochar properties for specific applications.

scholarly journals Correlations between physico-chemical properties and nickel adsorption parameters in soils used in sanitary landfill liners

2020 ◽  
Vol 34 (3) ◽  
pp. 275-284
Author(s):  
Ricardo Antonio Ferreira da Silva ◽  
Danilo Brito da Costa ◽  
William de Paiva ◽  
Márcio Camargo de Melo ◽  
Veruschka Escarião Dessoles Monteiro
Keyword(s):  
Chemical Properties ◽  
Bentonite Clay ◽  
Exchange Capacity ◽  
Isotherm Models ◽  
Sanitary Landfill ◽  
Adsorption Parameters ◽  
Clayey Sand ◽  
Landfill Liners ◽  
Physico Chemical ◽  
Nickel Adsorption

The adsorption of heavy metals by sanitary landfill liners represents a measure of protection of surface and groundwaters against contamination by metals, mitigating risks to public health. Hence, this research aimed to identify, from correlations, the influence of physico-chemical properties of soils applied in landfill liners using nickel adsorption parameters. Batch equilibrium tests with initial nickel concentrations of 45 to 1440 mg.L-1 were performed in clayey sand and bentonite clay soil, as well as in mixtures. Nickel adsorption parameters from Freundlich and Langmuir isotherm models were obtained, exhibiting a better adjustment in the Freundlich model based on R² and RMSE criteria. Thus, the addition of bentonite clay improved the adsorption to nickel, and the cationic exchange capacity (CEC) was the property that considerably influenced the metal retention in the studied soils.

scholarly journals Eudragit S100 Entrapped Liposome for Curcumin Delivery: Anti-Oxidative Effect in Caco-2 Cells

Coatings ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 114 ◽  
Author(s):  
Vincenzo De Leo ◽  
Sante Di Gioia ◽  
Francesco Milano ◽  
Paola Fini ◽  
Roberto Comparelli ◽  
...  
Keyword(s):  
Chemical Properties ◽  
Polymeric Coating ◽  
Scanning Calorimetry ◽  
Transmission Electron ◽  
Physico Chemical ◽  
Eudragit S100 ◽  
Natural Polyphenol ◽  
Anti Oxidant ◽  
Small Unilamellar Vesicles

Curcumin is a natural polyphenol with strong antioxidant activity. However, this molecule shows a very poor bioavailability, instability, and rapid metabolism in vivo. In this work curcumin was loaded in Eudragit-coated liposomes to create a gastroresistant carrier, able to protect its load from degradation and free it at the site of absorption in the colon region. Small unilamellar vesicles were prepared and coated with Eudragit by a pH-driven method. The physico-chemical properties of the prepared systems were assessed by light scattering, transmission electron microscopy, infrared spectroscopy, and differential scanning calorimetry. The uptake of vesicles by Caco-2 cells and the anti-oxidant activity in cells were evaluated. The produced vesicles showed dimensions of about forty nanometers that after covering with Eudragit resulted to have micrometric dimensions at acid pH. The experiments showed that at pH > 7.0 the polymeric coating dissolves, releasing the nanometric liposomes and allowing them to enter Caco-2 cells. Delivered curcumin loaded vesicles were then able to decrease significantly ROS levels as induced by H2O2 in Caco-2 cells. The proposed work showed the possibility of realizing effective gastroresistant curcumin liposome formulations for the delivery of antioxidant molecules to Caco-2 cells, potentially applicable to the treatment of pathological conditions related to intestinal oxidative stress.

scholarly journals Eosin Removal by Cetyl Trimethylammonium-Cloisites: Influence of the Surfactant Solution Type and Regeneration Properties

Molecules ◽  
2019 ◽  
Vol 24 (16) ◽  
pp. 3015
Author(s):  
Fethi Kooli ◽  
Souad Rakass ◽  
Yan Liu ◽  
Mostafa Abboudi ◽  
Hicham Oudghiri Hassani ◽  
...  
Keyword(s):  
Cation Exchange ◽  
Clay Mineral ◽  
Salt Solution ◽  
Cation Exchange Capacity ◽  
Chemical Properties ◽  
Surfactant Solution ◽  
Exchange Capacity ◽  
Maximum Temperature ◽  
Basal Spacing ◽  
Xrd Techniques

The effect of the counteranion of hexadecyltrimethylammonium salts on the physico-chemical properties of organoclays was investigated, using a selected natural clay mineral with a cation exchange capacity of 95 meq/100 g. The uptake amount of C16 cations was dependent on the hexadecyltrimethylammonium (C16) salt solution used, the organoclay prepared from C16Br salt solution exhibited a value of 1. 05 mmole/g higher than those prepared from C16Cl and C16OH salt solutions. The basal spacing of these organoclays was in the range of 1.81 nm to 2.10 nm, indicating a similar orientation of the intercalated surfactants, and could indicated that the excess amount of surfactants, above the cation exchange capacity of 0.95 meq/g could be adsorbed on the external surface of the clay mineral sheets. These organoclays were found to be stable in neutral, acidic, and basic media. The thermal stability of these organoclays was carried out using thermogravimetric analysis and in-situ X-ray diffraction (XRD) techniques. The decomposition of the surfactant occurred at a maximum temperature of 240 °C, accompanied with a decrease of the basal spacing value close to 1.42 nm. The application of these organoclays was investigated to remove an acidic dye, eosin. The removal amount was related to the initial used concentrations, the amount of the surfactants contents, and to the preheated temperatures of the organoclays. The removal was found to be endothermic process with a maximum amount of 55 mg of eosin/g of organoclay. The value decreased to 25 mg/g, when the intercalated surfactants were decomposed. The reuse of these organoclays was limited to four regeneration recycles with a reduction of 20 to 30%. However, noticeable reduction between 35% to 50% of the initial efficiency, was achieved after the fifth cycle, depending of the used organoclays.

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