A. M. El-kamash

Egyptian Atomic Energy Authority · Hot Laboratories and Waste Management Center

Zeolite A was chemically synthesized and evaluated, as inorganic ion exchange material, for the removal of cesium and strontium ions from aqueous solutions in both batch and fixed bed column operations. Batch experiments were carried out as a function of pH, initial ion concentration and temperature. Simple kinetic and thermodynamic models have bee...

Leaching characteristics of some radionuclides that are commonly encountered in radioactive waste streams from immobilized waste matrices in different cement-clay grouts have been assessed to investigate the influence of the clay additives on the leaching behavior of the solid waste matrices. The International Atomic Energy's Agency (IAEA) standard...

Cerium(IV) tungstate powder was chemically synthesized and exploited as adsorbent material for the decontamination study of cobalt and europium ions from radioactive waste solutions under simulated conditions using batch technique. The influences of pH, particle size and temperature have been reported. The uptake of europium was found to be slightl...

Pure zeolites can be synthesized from silica extracts obtained from fly ash by alkaline leaching. The extraction potential of industrial by-product fly ash was investigated under repeated fusion process conditions. The amount of extracted silica was 131.43 g/kg ash while the amount extracted alumina was limited to 41.72 g/kg ash. The results of zeo...

Permeable concrete is a class of materials that has long been tested and implemented to control water pollution. Its application in low-impact development practices has proved its efficiency in mitigating some of the impacts of urbanization on the environment, including urban heat islands, attenuation of flashfloods, and reduction of transportation...

Nano-zeolite is an innovative class of materials that received recognition for its potential use in water and tertiary wastewater treatment. These applications include ion-exchange/sorption, photo-degradation, and membrane separation. The aim of this work is to summarize and analyze the current knowledge about the utilization of nano-zeolite in the...

Nanostructured material chitosan polymer grafted with styrenesulphonate and acrylic acid as ion-imprinted polymer have been synthesised and developed by a new method that provides control over the size and chemical structure. The utilisation of high-intensity ultrasound has been investigated for the synthesis of a nanostructured polymer that is oft...

The development of cementitious materials remains a vital goal to produce valuable products with good mechanical, physical and chemical properties suitable for the safe disposal of concentrated radionuclides resulted from the treatment of contaminated solutions. In this paper, zeolite cement with good properties was laboratory synthesized from indu...

The development of cementitious materials remains a vital goal to produce valuable products with good mechanical , physical and chemical properties suitable for the safe disposal of concentrated radionuclides resulted from the treatment of contaminated solutions. In this paper, zeolite cement with good properties was laboratory synthesized from ind...

The last step in any radioactive waste management practice is the disposal activity which is designed to ensure isolation of these wastes under controlled conditions over extended time scale. Current designs of radioactive waste disposal facilities rely on the containment and confinement strategy through the use of multi-barrier concept in which en...

Several kinetic models were accustomed to check the experimental rate data and to examine the controlling mechanism of the sorption process for elimination of uranium and some lanthanides from aqueous solutions using synthesized sonicated emulsion polymer. The results showed thatpseudo-second-order and Elovich kinetic models provided a best-fit des...

Radionuclide sorption by natural and modified clays is extensively accepted to be an important process from the radioactive waste point of view. This work focused on modification of natural attapulgite with a layered double hydroxide to produce a novel chemisorbent for Sr2+, Ni2+, and Co2+ removal from multicomponent solution. The structural and su...

The original publication of this paper contains a mistake.

A composite polymer, hydroxyapatite/poly(acrylamide-acrylic acid), was synthesized by gamma-induced polymerization. The factors affecting the sorption process were evaluated. The removal increased with time and achieved equilibrium after 1 h for all initial concentration ranges (10–50 mg/L). The highest removal of Sr(II) was achieved using 50 mg/L...

Ion exchange technique is one of the widely applied conventional treatment options in nuclear industry, which is used to reduce the volume of aqueous radioactive waste streams, to separate isotopes and in decontamination operations. After being exhausted, spent exchangers are considered as radioactive waste and consequently they must be safely mana...

Recent advances in nanostructure materials have been developed by new synthetic method that provides control over size and chemical structure. The utilization of high intensity ultrasound has been investigated for synthesis of nanostructure polymer that is often unavailable by conventional methods. The preparation of emulsion polymer of carboxy met...

Ion exchange technique is one of the widely applied conventional treatment options in nuclear industry, which is used to reduce the volume of aqueous radioactive waste streams, to separate isotopes and in decontamination operations. After being exhausted, spent exchangers are considered as radioactive waste and consequently they must be safely mana...

Silica-based urea-formaldehyde (SiO2/UF) composite material was prepared and impregnated with organophosphorus extractant, namely; 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester, for removal of Eu3+ and Nd3+ from aqueous solutions. The sorption capacity of the impregnated SiO2/UF for Eu3+ and Nd3+ were determined and found to be 3.1 and 2.8 me...

Systems Engineering Lifecycle-Tools-Model Framework (SELTMF), based on integrating ISO/IEC 15288 with seven point of view architecture framework, is presented. The developed framework considers the service oriented point of view in addition to the common points of view suggested in the British Ministry of Defense architecture framework. Studied Key...

The present work was attempted to prepare three new sorbents including a poly(acrylamide–sodium styrene sulphonate) P(AM–SSS) hydrogel, a poly(hydroxamic acid–sodium styrene sulphonate) P(HA–SSS) modified polymeric resin and a poly(acrylamide–sodium styrene sulphonate–silicon oxide) P(AM–SSS–SiO2) composite by irradiation template polymerization. T...

The sorptive removal of cesium and cobalt ions from aqueous solutions in a fixed bed column packed with Lewatit S100® cation exchange resin has been investigated. A preliminary batch studies were performed to estimate the effect of pH and contact time on the sorption process. Results indicated that Cs+ and Co2+ could be efficiently removed using Le...

Leaching characteristics of ''1''3''7Cs from immobilized waste matrices in different cement-based grouts have been assessed to investigate the influence of the additives on the leaching behavior of the solid waste matrices. The International Atomic Energy's Agency (IAEA) standard leach method has been employed to study the leach pattern of 137Cs ra...

Radioactive liquid waste treatment is a subject that have received considerable attention worldwide in recognition of its importance for the protection of human health and the environment from adverse effects of radiation associated with these wastes. In this work, the radioactive waste management policy principles will be presented briefly, and an...

Simultaneous Gamma irradiation was used to prepare Epoxy/Pac porous resin. Characterizations of the polymer using Fourier Transform Infrared (FTIR), Thermogravimetric analysis (TGA), scanning electron microscope were performed. The sorption potential of polymer for removal of Cs+ from liquid solutions has been investigated. The influences of pH, co...

Sorption isotherm studies were performed using the batch technique to obtain equilibrium data for removal of Cs+ and Sr2+ ions from aqueous solutions using fly ash based NaA-X zeolite blend. To determine the chemical conditions at which Cs+ and Sr2+ are effectively sorbed onto the studied ion exchanger, preliminary batch experiments at different pH...

Leach characteristics of 137Cs and 60Co radionuclides from both ordinary Portland cement and cement mixed with two different ratios of blast furnace slag and ceramic sludge have been studied using IAEA’s standard leach method. A mathematical model has been simulated to predict the release rate of each nuclide from cylindrical geometry waste matrix,...

Simultaneous Gamma irradiation was used to prepare Epoxy/Pac porous resin. Characterizations of the polymer using Fourier Transform Infrared (FTIR), Thermogravimetric analysis (TGA), scanning electron microscope were performed. The sorption potential of polymer for removal of Cs + from liquid solutions has been investigated. The influences of pH, c...

The underground disposal of radioactive waste is based upon a multibarrier concept. For long-term performance assessment of radioactive repositories, knowledge concerning the sorption of radionuclides in backfill materials is required. As a part of the multibarrier system for effective isolation of radioactive waste in a repository, Zeolite NaA–X b...

Thermodynamic and kinetic investigations on the removal of Eu3+ ions from aqueous waste solution using bentonite and sandstone, as local clay minerals, has been done using batch technique. The influences of ph, contact time between liquid and solid phases, initial metal ion concentration, and temperature have been evaluated. Pseudo first-order and...

Ion exchange experiments between synthetic zeolite A and aqueous solutions of cesium and strontium ions were conducted at constant total ion concentrations of 0.1 N and at different temperatures in the range from 25 to 60 degree C. Thermodynamic equilibrium constants, calculated from the corresponding Kielland's plots, were used for the calculation...

Over the past 40 years, a considerable amount of solid radioactive waste has been generated in Egypt from a variety of nuclear technology applications in research, medicine, and industry. The Hot Laboratory and Waste Management Center at Inshas, Cairo, has started to build an integrated waste management system to ensure the safe management of this...

Zeolites are preferred ion exchange materials for the removal of radioisotopes from aqueous nuclear wastes because of their selectivity, radiation and temperature stability, and good compatibility with the cement matrix. Loaded materials, which are not regenerated, are preferably embedded in a solid matrix prior to ultimate storage in a repository....

Summary The batch removal ofCs+, Sr2+, Ca2+and Mg2+ions from aqueous solutions using synthetic zeolite A was investigated. The influence of the initial ion concentration, pH and temperature was studied. The obtained isotherm data have been correlated with Langumir, Freundlich, and Dubinin-Radushkevich(D-R) isotherm models. The effect of the tempera...

The batch removal of Cs+, Sr2+, Ca2+ and Mg2+ ions from aqueous solutions using synthetic zeolite A was investigated. The influence of the initial ion concentration, pH and temperature was studied. The obtained isotherm data have been correlated with Langumir, Freundlich, and Dubinin-Radushkevich (D-R) isotherm models. The effect of the temperature...

Summary Kinetics and equilibrium studies on the sorption of uranium and thorium ions were carried out from nitric acid solutions by tri-n-butyl phosphate (TBP) loaded supported sorbent, commercially known as Egy-Sorb, using batch technique. Analysis of the rate data in accordance with three kinetic models revealed that the particle diffusion proces...

The sorptive removal of zinc and cadmium ions from aqueous solutions using synthetic zeolite A was investigated. Experiments were carried out as a function of solute concentration and temperature (298-333 K). Several kinetic models were used to test the experimental rate data and to examine the controlling mechanism of the sorption process. Various...

Preparation and characterization of zeolite-A exchanger were carried out for kinetic studies on the removal of cesium and strontium ions from aqueous solutions. Ion exchange experiments were constant ion-concentration and different temperatures in the range from 25 c degree to 60{+-} c degree. Analysis of the respective rate data in accordance with...

Equilibrium measurements on the sorption of uranium and thorium ions from nitric acid solutions using di(2-ethyl hexyl) phosphoric (HDEHP) impregnated activated carbon have been done using batch technique. Experimental isotherms, Ferundlish, and Dubinin-Radushkevich (D-R) isotherm models. Of the models tested, D-R expression was found to represent...

Extraction chromatography has been used to study the extraction of both U(VI) and U(IV) from nitric acid solutions using TBP solvent impregnated polyacrylic acid polymer (SM-7) as inert supporting material. Batch kinetic and breakthrough column experiments were carried out to explain the mechanistic aspects of the extraction process, obtain thermod...

Leach characteristics of 137Cs and 60Co radionuclides from both ordinary Portland cement and cement mixed with two different ratios of silica fume and ilmenite have been studied using International Atomic Energy's (IAEA) standard leach method. A mathematical model has been simulated to predict the release rate of each nuclide from cubic geometry wa...

Thermodynamic investigation of the extraction of both uranium(VI) and uranium(IV) from nitric acid solutions using tri-n-butyl phosphate (TBP) loaded on polyacrylic acid polymer (SM-7) as an inert supporting material has been done using batch technique. The effect of temperature on the equilibrium extraction values has been utilized to evaluate the...

The disposal of low and intermediate level radioactive wastes in shallow land burial sites has received strong scrutiny with respect to waste integrity and radionuclides migration through the engineering barrier to the geosphere. The aim of this study is to determine the transient mass release rates of radionuclides from an engineered disposal faci...

In treatment of liquid radioactive wastes by ion exchange technique, specific attention is drawn to the simulation of exchange system behavior. Mathematical models are particularly useful in the design and optimization of ion exchange columns to predict the characteristics of the breakthrough curve under a given set of conditions. A systematic mat...

With the ever-growing generation and stockpiling of hazardous wastes, safe storage and disposal of waste forms become extremely important. Waste forms that are placed in the environment must be engineered so that release of hazardous materials is minimized. Methods for realistic estimation of contaminant release must be developed to meet regulation...

A framework is developed to provide predictions of multicomponent ion-exchange equilibria from binary data. Our input data were taken from published experimental results on the ion-exchange equilibria of the binary systems Sr2+–Na+, Cs+–Na+, and Sr2+–Cs+ on chabazite zeolite. These systems exhibit nonideal characteristics in both solid and liquid p...

An iterative model for prediction of ion-exchange equilibria over a wide range of total concentrations from one experimental isotherm has been proposed. Using thermodynamic parameters derived from the 0.2 N concentration of the system Sr2+/Na+/ chabazite, the model was applied to predict isotherm values at 0.05 and 0.5 N. These predicted isotherms,...