title: Preconcentration and determination of rare-earth elements in iron-rich water samples by extraction chromatography and plasma source mass spectrometry (ICP-MS).
abstract: A 100-fold preconcentration procedure based on rare-earth elements (REEs) separation from water samples with an extraction chromatographic column has been developed. The separation of REEs from matrix elements (mainly Fe, alkaline and alkaline-earth elements) in water samples was performed loading the samples, previously acidified to pH 2.0 with HNO(3), in a 2ml column preconditioned with 20ml 0.01M HNO(3). Subsequently, REEs were quantitatively eluted with 20ml 7M HNO(3). This solution was evaporated to dryness and the final residue was dissolved in 10ml 2% HNO(3) containing 1mugl(-1) of cesium used as internal standard. The solution was directly analysed by inductively coupled plasma mass spectrometry (ICP-MS), using ultrasonic nebulization, obtaining quantification limits ranging from 0.05 to 0.10 ngl(-1). The proposed method has been applied to granitic waters running through fracture fillings coated by iron and manganese oxy-hydroxides in the area of the Ratones (Cáceres, Spain) old uranium mine.
authors.affiliation: Unit of Mass Spectrometry and Geochemical Applications, Chemistry Division, Department of Technology, CIEMAT, Avda. Complutense 22, 28040 Madrid, Spain.
authors.forename: Carolina
authors.initials: C
authors.lastname: Hernández González
authors.forename: Alberto J Quejido
authors.initials: AJ
authors.lastname: Cabezas
authors.forename: Marta Fernández
authors.initials: MF
authors.lastname: Díaz