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Elwakeel K.Z.,Egyptian Water and Wastewater Regulatory Agency | Rekaby M.,National Research Center of Egypt
Journal of Hazardous Materials

Glycidyl methacrylate/methelenebisacrylimide resin loaded with tetraethelenepentamine ligand was prepared and investigated. The adsorption characteristics of the obtained resin towards Reactive Black 5 (RB5) from aqueous solutions at different experimental conditions were established by means of batch and column methods. The mechanism of interaction between RB5 and resin's active sites was discussed. The resin showed high affinity for the adsorption of RB5 where an uptake value of 0.63. mmol/g was reported for the obtained resin, at 25°C. The kinetics and thermodynamic behavior of the adsorption reaction were also defined. These data indicated an endothermic spontaneous adsorption process and kinetically followed the pseudo-second order model. Breakthrough curves for the removal of RB5 were studied at different flow rates and bed heights. The critical bed height for the studied resin column was found to be 0.764. cm at flow rate of 8. mL/min. The adsorbed dye was eluted from the investigated resin effectively. Regeneration and durability of the loaded resin towards the successive resin were also clarified. © 2011 Elsevier B.V. Source

Elwakeel K.Z.,Egyptian Water and Wastewater Regulatory Agency | Yousif A.M.,Menoufia University
Water Science and Technology

Thermally treated egg shell materials were prepared at different temperatures. The samples were investigated by means of FT-IR and thermogravimetric analysis (TGA). The adsorption behaviour of malathion on egg shell and its thermally treated samples was studied using batch method and gave uptake capacities up to 0.964 mmol/g. Adsorption kinetics as well as the adsorption isotherms were discussed. Regeneration of the loaded adsorbent beads towards the successive cycles was also clarified. The adsorption of malathion is maintained untill the third cycle without a significant activity loss. © IWA Publishing 2010. Source

Elwakeel K.Z.,Egyptian Water and Wastewater Regulatory Agency

Chitosan was cross-linked using glutaraldehyde in the presence of magnetite. The resin obtained was chemically modified through the reaction with tetraethylenepentamine followed by glycidyl trimethylammonium chlorid to produce chitosan bearing amine (R1) and chitosan bearing both amine and quaternary ammonium chloride moieties (R2), respectively. The quaternary amine resin (R2) showed a higher affinity towards the uptake of Cr(VI) from alkaline medium, where an uptake value of 2.8 mmol/g was reported at pH 8 and 25 °C. The nature of interaction of R2 with chromate in alkaline medium was clarified. The resin Kinetics at different temperatures and thermodynamic parameters of the uptake process in alkaline medium were obtained. The uptake of Cr(VI) from different electrolyte solutions was studied. Regeneration curves for the desorption of Cr(VI) from R2 were studied. The adsorbed chromate anions was regenerated effectively (desorption ratio ~ 98%) using a mixture of 2 M NaCl and 0.5 M NaOH. © 2009 Elsevier B.V. All rights reserved. Source

Elwakeel K.Z.,Port Said University | El-Sadik H.A.,Egyptian Water and Wastewater Regulatory Agency | Abdel-Razek A.S.,Egypt Atomic Energy Authority | Beheary M.S.,Port Said University
Desalination and Water Treatment

Cellulosimicrobium cellulans (C. cellulans) was isolated from radioactive wastes and identified by Biological examination. The investigation of the removal of thorium from aqueous solutions was carried out using the isolated living and dead C. cellulans. The biosorption of thorium was studied using different thorium ion concentrations. Electron microscopic examinations of both living and dead C. cellulans before and after biosorption of thorium ions were done to locate the sites of metal ion biosorption and to find the difference between living and dead bacterial cells. The obtained results showed that living and dead C. cellulans could sorp 151.94 and 220.56 mg/g, respectively. The kinetic behavior and biosorption isotherm were defined. These data kinetically followed the pseudo-second-order model and indicated a good fitness with the Langmuir model. © 2012 Desalination Publications. All rights reserved. Source

Elwakeel K.Z.,Egyptian Water and Wastewater Regulatory Agency
Journal of Dispersion Science and Technology

Chitosan is a polysaccharide formed mainly from repeating residues of D-glucosamine, having primary amino groups. It is of great interest not only as an underutilized resource, but also as a new functional material of high potential in various fields, and recent progress in chitin chemistry is quite noteworthy. The purpose of this review is to take a closer look at chitosan application in water technology based on (a) its ability to bind toxic pollutants, (b) the mod of chitosan modification, (c) the nature of the interaction of chitosan with different pollutants, and (d) chitosan regeneration and recycling. © Taylor & Francis Group, LLC. Source

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