Plutonium and uranium adsorption on monosodium titanate

Adsorption of Pu and U onto monosodium titanate (MST) in alkaline salt solution was measured. Changes in MST particle size distribution do not significantly affect the loadings of actinides. Max loading of plutonium-239 is 0.68 wt% at 0.79 mg/L Pu, below the infinitely safe value of 0.80 wt%. Max loading of uranium-235 onto MST is 1.4 wt% at a concentration of 20.3 {plus_minus} 2.0 mg/L U, slightly higher than the calculated infinitely safe limit of 1.2 wt%. Experimental data indicated there is competition between plutonium and uranium for sites on the MST, and that the loading will favor the higher concentration species. Since the solubility of uranium is 10--100 times higher than of plutonium, uranium will be loaded to its maximum limit, but plutonium will be below its maximum limit. To ensure that the concentration of fissile materials cannot exceed nuclear safety limits, it is recommended that plutonium and uranium solubility tests be conducted with solutions which bound the compositions of waste which will be treated in ITP process.