Sorption Behaviour of Molybdenum on Different Metal Oxide Ion Exchangers

Thermal Desorption of Molybdenum (VI)-Oxide from Loaded Metal Oxide Ion Exchangers

“…The arithmetic mean between lower and upper limit of the used particle size interval (sieve fraction) was taken as the mean particle diameter. specific surface area) compared to A1 2 0 3 , as it had been determined during the Mo sorption experiments [9]. From this fact it can be supposed that the molybdate species are sorbed to a larger extent at the outer surface of the particles, if the same Mo-loading like in the A1 2 0 3 -system is used.…”

“…Due to these facts and the wellknown porous structure of A1 2 0 3 ion exchanger (specific surface area = 112,6 m 2 g" 1 [9]) it was rather obvious that the volatilization rate of molybdenum(Vl)-oxide was controlled in this case by diffusion of the species inside the A1 2 0 3 particles.…”

“…This is the case at 1250°C in a N 2 /H 2 0-atmosphere using a 40 minutes sublimation time. For all the data discussed up to here a loading of 4,7 mg Mo/g oxide had been used, a value which corresponds to the breakthrough capacity of Sn0 2 in 0,02 M HN0 3 [9]. In Figure 10 the Mo-loading dependent yields of both oxides are plotted.…”

“…Previously performed distribution experiments with acidic and amphoteric metal oxide ion exchangers showed, that A1 2 0 3 and Sn0 2 are the most suitable materials with regard to a good Mo-sorption capacity, fast sorption rate, thermal stability and easy separation from the liquid phase by filtration [9]. The experiments described in this paper give as a result whether these two oxides can also be used for the second part of the procedure: the thermal desorption of the molybdenum(VI)-oxide.…”

Separation of Fission 99Mo on Charcoal Columns Impregnated with Tin(IV) Chloride for Use in Preparation of 99mTc Generators

“…The obtained "Mo eluates are usually seriously contaminated with the radionuclides 131,132^ 132 Τβ) 95^ 95^ 103 Ru> ^ ^ 2γ> 29]. Therefore, additional purifications of "Mo are needed using repeated cyclings on different adsorbents and high temperature volatilization [10,12,20,21,24,25,28,[30][31][32][33], In previous work, the sorption behaviour of "Mo(VI) and some relevant fission products on charcoal impregnated with tin(IV) chloride in HCl solutions was investigated [34,35], The aim of this work is to investigate the separation of "Mo from fission products on impregnated charcoal columns and to evaluate the separated "Mo for use in preparations "Mo/ 99m Tc generators.…”