Synthesis Of Thorium Phosphate Diphosphate And Zirconium Diphosphate, And The Sorption Of Eu(â…¢) And Am(â…¢) On The Synthesized Sorbents

The sorption characteristics of lanthanides element Eu (â…¢) and actinides element Am (â…¢) onto synthesis absorbent of Th₄(PO₄)₄PaO₇ and ZrP₂O₇ were studied by a batch technique.Sorption of Eu(â…¢) and Am(â…¢) on thorium phosphate diphosphate as a function of equilibrium time, the ratio of adsorbent mass to solution volume (m/v), pH, ionic strength and fulvic acid (FA) were studied under ambient condition using batch technique. The experimental results indicated that the sorption rate of Eu(â…¢) and Am(â…¢) on thorium phosphate diphosphate increased with increasing sorption time in the first 10 hours. 16hours and 20hours were selected as sorption equilibrium time, respectively. The sorption rate of Eu(â…¢) and Am(â…¢) on thorium phosphate diphosphate increased with increasing m/v from 1.67g/L to 20.00g/L. 10.00g/L was chosen as the ratio of solid to liquid of follow-up sorption experiment. Sorption of Eu(â…¢) and Am(â…¢) on thorium phosphate diphosphate were strongly affected by pH values , as compared Eu(â…¢) and Am(â…¢) sorption on the same adsorbent, the Eu(â…¢) and Am(â…¢) sorption on thorium phosphate diphosphate had the similar pH sorption curves. The sorption of Eu(â…¢) and Am(â…¢) increased steeply with increasing pH from 2 to 5. When other conditions were the same, the sorption rate of Eu(â…¢) and Am(â…¢) on thorium phosphate diphosphate decreased with increasing ionic strength from 0.01mol/L to 0.1mol/L KNO₃. The positive effect of FA on the sorption of Eu(â…¢) and Am(â…¢) on thorium phosphate diphosphate were found from the compared studies.Sorption of Eu(â…¢) and Am(â…¢) on zirconium diphosphate as a function of equilibrium time, the ratio of adsorbent mass to solution volume (m/v), pH, ionic strength and fulvic acid (FA) were studied under ambient condition using batch technique. The experimental results indicated that 15 hours was chosen as sorption equilibrium time of Eu(â…¢) and Am(â…¢) on zirconium diphosphate. The sorption rate of Eu(â…¢) and Am(â…¢) on zirconium diphosphate increased with increasing m/v from 1.25g/L to 30.00g/L. 5.00g/L was selected as the ratio of solid to liquid of follow-up sorption experiment. pH values was the impact of one of the main sorption factors, as compared Eu(â…¢) and Am(â…¢) sorption on the same adsorbent, the Eu(â…¢) and Am(â…¢) sorption on zirconium diphosphate had the similar pH sorption characteristics. The sorption rate of Eu(â…¢) and Am(â…¢) increased steeply with increasing pH from 1 to 3. When other conditions were the same, the sorption rate of Eu(â…¢) and Am(â…¢) on zirconium diphosphate maintained invariable basically with increasing ionic strength from 0.01mol/L to 0.1mol/L KNO₃. The positive effect of FA on the sorption of Eu(â…¢) and Am(â…¢) on zirconium diphosphate were found from the compared studies.It was assumed that surface complexes were formed on the surface of thorium phosphate diphosphate and zirconium diphosphate. The study of adsorbent surface characteristics and sorption mechanism are the important aspects of farther experiment.