الفهرس 
صفحة العنوانOnly 14 pages are availabe for public view
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Abstract
Aim of the Work
Recently, pollution with rare earth and radioactive elements has been a matter of great concern for the last decades for human health and animals. Uranium and thorium are the most radioactive elements affecting the environment. They have the ability to change genetic materials. Moreover, trivalent lanthanides have the ability to alter or even inhibit the action of various enzymes in human body.
Nowadays, Due to the high advantages of adsorption processes like low cost, simple selectivity, high efficiency, easy operation, and rapid kinetics;it becomes a suitable method for the removal of pollutant and toxic metal ions from wastewater.
In our study, modified adsorbent material has been investigated with some rare earths and some actinides to evaluate the possibility for removal of such dangerous elements from our environmental resources.
The present study aimed to explore the applicability of 8-hydroxyquinoline modified Na-bentonite for the removal of some actinides e.g. (thorium and uranium) and some lanthanides e.g. (yttrium, neodymium, samarium, gadolinium, and Lutetium) from their aqueous solutions. Moreover, the kinetics, isotherm and thermodynamic characteristics of the investigated elements will be discussed.
Recently, more and more lanthanides and actinides enter the environment through various pathways as a result of rapid increase of the utilization of their resources and their applications in many fields of modern industry and daily life. The potential use of inexpensive and available inorganic sorbent;8-hydroxyquinoline modified bentonite (HQ-bentonite) for removal of some lanthanides e.g. Y(III), Nd(III), Sm(III), Gd(III) & Lu(III) and actinides e.g. Th(III) & U(IV) from their aqueous solutions has been investigated using the adsorption method. The adsorption processes were studied as a function of initial pH, shaking time, initial metal ion concentration, adsorbent weight and temperature for each element to determine their optimum removal conditions. Freundlich and Langmuir adsorption isotherms were used for modeling equilibrium data. The sorption results demonstrated that the sorption of actinides and lanthanides onto HQ-bentonite correlated better with the Langmuir isotherm than Freundlich isotherm. The kinetics of the adsorption processes has been studied to examine the controlling mechanism of the adsorption process. The thermodynamic parameters: H°, S° and G° for the sorption process have been calculated for each element. Desorption of each element from the surface of the adsorbent material was studied to determine the optimum desorption conditions.