Alpha spectroscopic analysis of actinides (Th, U and Pu) after separation from aqueous solutions by cation-exchange and liquid extraction

Selective separation of actinyl(V,VI) cations from aqueous solutions by Chelex-100

“…2 × 10 −6 mol l −1 for samarium, thorium and uranium-238, and 0.1 Bq l −1 for americium and neptunium and uranium-232). The separation of the actinide/lanthanide cations from the aqueous matrix was performed by cation exchange using Chelex-100 resin [12][13][14]. 0.3 g of Chelex-100 resin were added to a 100 ml sample contained in a polypropylene beaker and stirred on a magnetic stirring table.…”

“…For the alpha spectroscopic measurement he acidic solution was evaporated to incipient dryness and the residual was dissolved in 10 ml of 0.15 M (NH 4 ) 2 SO 4 solution. From this solution, uranium was directly electrodeposited on a stainless steel disc (diameter of the active area 10 mm) at a voltage of 15 V and a current of 0.4 A for 2 h [13,14]. All measurements were performed in triplicate and the error bars in the graphs correspond to the standard deviation, which was calculated based on the repeated measurements.…”

“…Chelex-100 is a weak acidic, complexing resin, which has been extensively investigated with respect to the separation and preconcentration of uranium and other actinides prior photometric [10,11] and radiometric analysis using liquid scintillation counting (LSC) [12] and alpha-spectroscopy [13,14]. These studies have shown that Chelex-100 can be effectively used for the separation and preconcentration of uranium from laboratory and natural waters.…”

Automating Radiochemical Analysis

“…Thus, 4,4 0 -(5 0 )-bis(tert-butylcyclohexano)-18-crown-6 solution in 1-octanol has been used as extractant for the selective isolation of strontium [10], di-2-ethylhexylphosphoric acid (HDEHP) for yttrium extraction [11], tri-n-octylphosphine oxide and tri-n-butyl phosphate (TBP) were used as complexing ligands of uranium [17], TBP in dodecane has been applied to the extraction of uranium, thorium and plutonium [18,19], and a mixture of aliquatÒ as extractant and 2-propanol as disperser solvent can be used to isolate technetium. Thus, 4,4 0 -(5 0 )-bis(tert-butylcyclohexano)-18-crown-6 solution in 1-octanol has been used as extractant for the selective isolation of strontium [10], di-2-ethylhexylphosphoric acid (HDEHP) for yttrium extraction [11], tri-n-octylphosphine oxide and tri-n-butyl phosphate (TBP) were used as complexing ligands of uranium [17], TBP in dodecane has been applied to the extraction of uranium, thorium and plutonium [18,19], and a mixture of aliquatÒ as extractant and 2-propanol as disperser solvent can be used to isolate technetium.…”

Comparative study of different analytical methods for the determination of 238U, 234U, 235U, 230Th and 232Th in NORM samples (Southern Catalonia)

“…After the sample digestion, there are different alternatives for the radiochemical separation of the different radioisotopes (Eikenberg et al, 2009;Palomo et al, 2010;Reis et al, 2011). The most widely used methodologies are based on the use of liquideliquid extraction (LLE) and, in the case of uranium and thorium separation, one of the most commonly used strategies is performing the extraction with tri-n-butyl phosphate (TBP) and xylene and then a purification process by using an ionexchange material (Kiliari and Pashalidis, 2010;Lozano et al, 2010;Palomo et al, 2010). However this approach has some disadvantages, such as the use of large amounts of organic solvents, which can be harmful.…”