title: Uranium and thorium sequential separation from norm samples by using a SIA system.
abstract: This study presents a sequential radiochemical separation method for uranium and thorium isotopes using a novel Sequential Injection Analysis (SIA) system with an extraction chromatographic resin (UTEVA). After the separation, uranium and thorium isotopes have been quantified by using alpha-particle spectrometry. The developed method has been tested by analyzing an intercomparison sample (phosphogypsum sample) from International Atomic Energy Agency (IAEA) with better recoveries for uranium and thorium than the obtained by using a classical method (93% for uranium using the new methodology and 82% with the classical method, and in the case of thorium the recoveries were 70% for the semi-automated method and 60% for the classical strategy). Afterwards, the method was successfully applied to different Naturally Occurring Radioactive Material (NORM) samples, in particular sludge samples taken from a drinking water treatment plant (DWTP) and also sediment samples taken from an area of influence of the dicalcium phosphate (DCP) factory located close to the Ebro river reservoir in Flix (Catalonia). The obtained results have also been compared with the obtained by the classical method and from that comparison it has been demonstrated that the presented strategy is a good alternative to existing methods offering some advantages as minimization of sample handling, reduction of solvents volume and also an important reduction of the time per analysis.
authors.affiliation: Universitat Rovira i Virgili, Marcel·lí Domingo s/n, 43007 Tarragona, Spain; Unitat de Radioquímica Ambiental i Sanitària (URAIS), Consorci d'Aigües de Tarragona (CAT), Ctra Nacional 340, km 1094, 43895 L'Ampolla, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Mola
authors.forename: A
authors.initials: A
authors.lastname: Nieto
authors.forename: A
authors.initials: A
authors.lastname: Peñalver
authors.forename: F
authors.initials: F
authors.lastname: Borrull
authors.forename: C
authors.initials: C
authors.lastname: Aguilar
mesh_terms: D000512:Alpha Particles; D017022:Flow Injection Analysis / Q000379:methods*; D019015:Geologic Sediments / Q000032:analysis; D012722:Sewage / Q000032:analysis; D013030:Spain; D013057:Spectrum Analysis / Q000379:methods; D013910:Thorium / Q000032:analysis* / Q000302:isolation & purification; D014501:Uranium / Q000032:analysis* / Q000302:isolation & purification; D014875:Water Pollutants, Radioactive / Q000032:analysis* / Q000302:isolation & purification; D018508:Water Purification
chemical_list: D012722:Sewage; D014875:Water Pollutants, Radioactive; D014501:Uranium; D013910:Thorium
keywords: Alpha-particle spectrometry; Naturally occurring radioactive material; Sequential injection analysis; UTEVA resin