Highly efficient separation of yttrium from concentrated strontium aqueous solution by novel silica-based HDEHP-impregnating adsorbent

As the primary fission product in spent nuclear fuel being generally filed into the high-level liquid waste, the 90 Sr recovered from the reprocessed nuclear fuel could be a significant source for producing 90 Y nuclide (the decay daughter). It presents as one favorable therapeutic radionuclide candidate for radiolabeling of pharmaceuticals in widespread clinical application. Under this situation, a novel silica-based adsorbent (HDEHP/SiO 2 -P) was developed for selective separation of Y 3+ from concentrated Sr 2+ in aqueous solution. Batch adsorption process was investigated under different parameters of acid type and strength, contact time, temperature, ionic concentration and molar ratio etc. It was confirmed that, the HDEHP/SiO 2 -P had highly selective properties toward Y 3+ over Sr 2+ in different acidic medium (i.e., hydrochloric, nitric and acetic acid), with maximum adsorption capacity 34.05 mg Y 3+ /g. Sorption isotherms and uptake kinetics, were better fitting for Langmuir monomolecular layer adsorption mode and the pseudo-second order (PSORE) kinetic model respectively. The sorbent shows high SF Y/Sr of 1.93 × 10 3 even at a Sr-Y molar ratio of 2 × 10 3 . Moreover, dynamic separation of trace amount of Y 3+ from the concentrated Sr 2+ aqueous solution was successfully validated by the column test, in which 100 % Y 3+ was recovered. The produced eluate is characterized by a sharp elution curve without Sr trailing under high acidic conditions of 6 M HCl. All these results would promisingly promote the application of the developed material and chromatographic approach to facilely obtain the adequate quantities of 90 Y with required radiochemical purity for its widespread clinical use.