99Mo/99mTc generators optimizations investigations: Characterization of alumina with deferments particles sizes and kinetic studding of molybdenum adsorption on alumina
Currently, in Morocco the demand for radioisotopes and radiolabelled compounds is steadily increasing with the emergence of new nuclear medicine centres. To support this evolution, the National Center for Nuclear Energy, Sciences and Technologies (CNESTEN-Morocco). was placed an ambitious program for the development and manufacture of radioisotopes for medical purposes. The most important one is technetium-99m generators production. In order to improve the efficiency of technetium generators manufacturing in CNESTEN-Morocco), we evaluated the influence of different parameters of molybdenum adsorption by alumina. Firstly, samples in different conditions have been investigated in order to determine the intrinsic surface properties of α-Al2O3, which is a point zero charge, isoelectric point and the number of active sites. These studies show that α-Al2O3 with 63-200 μm of particles seizes oxide, have the best intrinsic surface properties. In the other hand, several parameters have been studied to optimize the fixation of molybdenum on alumina involved for adsorption evaluation, such as: pH, contact time, partial seize of the oxide, chlorination, electrolyte concentration. In addition, ATR-FTIR spectra were investigated to inspect the molybdenum adsorption on the oxide. Finally, we have been able to define the behaviour of the molybdenum-alumina complex according the variations of pH and contact time. The influence of the mixture of partial sizes was carried out. The mechanism of adsorption of molybdenum is greatly influenced by pH modification. This investigation needs a very large number of experiences. For many reasons of radio protection, radioactive waste management and economics investment, the study was divided into two parts. In the first one “cold investigation” we used stable molybdenum. In the second one “hot investigation” we reproduced the most relevant experiments in hot cells using radioactive molybdenum 99mMo solutions.