Combination of N'-N'-di-n-hexyl-thiodiglycolamide and 2,2'-[(2-ethylhexyl)imino]bis[N,N-bis(2-ethylhexyl) acetamide] for the enhanced adsorption of palladium ions from simulated high-level liquid waste

A N'-N'-di-n-hexyl-thiodiglycolamide and 2,2'-[(2-ethylhexyl)imino]bis[N,N-bis(2-ethylhexyl)acetamide] impregnated porous silica-based adsorbent was prepared for enhancing the adsorption of palladium ions from simulated high-level liquid waste. The adsorbent exhibited a relatively fast palladium response and selectivity without the use of additional modification reagents. Palladium ions were adsorbed over a wide nitric acid range of 0.6-5 M and a broad temperature range of 288-323 K. The uniform distribution of adsorbed palldium ions onto the study adsorbent was confirmed by PIXE. Successful recovery of more than 90% of the palladium ions was achieved using 0.1 M thiourea via separation by column experiments. Based on the obtained data, it is expected that the prepared adsorbent can be used for the practical separation of palladium ions from high-level liquid waste. (author)