الفهرس 
AbstractOnly 14 pages are availabe for public view
 |  | from | 132 |  |  |
| | | from | 132 | | |
Abstract
Separation and fixation of fission products and other radionuclides are very important in the nuclear fields. Thus, the present study was aimed to develop simple, low cost and convenient methods for the removal of some radionuclides from radioactive liquid waste. A further goal was aimed to prepare a thermally stable, high resistance for ionizing power and temperatures inorganic ion exchanger for use in the treatment of certain radionuclides in the radioactive liquid waste. Thus, the work presented in this thesis was focused on three main topics: I A brief literature survey on the application of inorganic ion exchanger and polyurethane foams immobilizing hyDROPhobic organic or inorganic species for the quantitative enrichment, recovery and determination of various inorganic solutes from various matrices including radioactive liquid waste has been reviewed. The preparation and characterization of various inorganic and organic ion exchangers have been reviewed. II Preparation and characterization of the inorganic ion exchanger, titanium (IV) molybdate employing Xray diffraction, Xray florescence, thermal analysis and infrared spectrometry were successfully achieved. Xray diffraction data showed that, the prepared titanium molybdate has amorphous structure with a chemical formula Ti6Mo5O27.14.2H2O. The prepared exchanger was found stable in water, insoluble in HCl or HNO3 up to 2M and partially soluble in HNO3 and HCl up to 6M concentration. In the FTIR spectrum , two well defined vibration modes in the range 500700 and 750850 Cm1 were observed and safely assigned to TiO and MoO bonds in MoO4 groups, respectively. III The capacity measurements of titanium molybdate ion exchanger for sodium and uranium were found high. Thus, the influence of various parameters involving the retention performance of titanium molybdate ion exchanger for sodium and uranium from the aqueous solution were critically tested. The log Kd for sodium and uranium cations onto titanium molybdate varied linearly with pH and the slopes of the straight lines were found equal the valency of each cation confirming the ideality of the prepared titanium (IV) molybdate exchanger. The sorption isotherm of sodium and uranium (102104M) onto titanium (IV) molybdate ion exchanger increased linearly with increasing the equilibrium concentration of the metal ions. A plot of log Qe versus log Ce gives a straight line confirming Freundlich adsorption isotherm. The thermodynamic parameters ?E, ?H, and ?S for the retention of sodium and uranium ions onto the exchanger were determined. The value of ?H for uranium and sodium ions uptake onto the exchanger were found equal 13.87 and 26.2 Kjmol1 indicating that uranium and sodium react endothermically and exothermically with titanium molybdate, respectively. IV The kinetics and mechanism of uranium and sodium ions uptake onto the prepared exchanger titanium molybdate were critically investigated after providing the conditions that permit particle diffusion mechanism. The rate of the ion exchange reaction increased with raising the reaction temperature. The rate constants of the exchange of uranium and sodium ions onto the ion exchanger did not depend on the solution concentration. The diffusion coefficients of uranium and sodium ions uptake by the prepared ion exchanger were calculated. V The retention profile of uranium species in the aqueous solution by polyurethane foams loaded with crown ether and trinbutyl phosphate showed a reasonable percent removal of uranium species from the aqueous test solution. Thus, the influence of various parameters, e.g. solution pH, shaking time, batch factor (v/m) and sorbent dose were investigated. The retention was found fast and reached equilibrium in 50 min. Sorption isotherm of uranyl ions from the aqueous solution was achieved and subjected successfully to Freundlich isotherm. The data suggested a dual sorption mechanism involving solvent extraction and an added component related to the surface area of the polyurethane foams. Chromatographic behaviour of uranium on a crown ether loaded foam packed column was studied. Quantitative sorption and recovery (99.5 1.2) of uranium (VI) ions from the aqueous solution were achieved successfully employing acetone as eluting agent. The HETP, the number of theoretical plates (N), the breakthrough capacity and the critical capacity values were found equal 1.1 0.01mm, 66 4.5, 58.3 mg/g and 41.66 mg/g, respectively.