title: Determination of traces of 237Np in environmental samples by ICP-MS after separation using TOA extraction chromatography.
abstract: A simple, rapid, cost-efficient, and robust method for separation of 237Np with an extraction chromatographic column (TOA: tri-n-octylamine on Teflon powder) is outlined in detail and further improved for direct ICP-MS analysis. The column efficiently retained 237Np in 2 mol L(-1) HNO3 medium and all of the 237Np was easily eluted with 0.02 mol L(-1) oxalic acid in 0.16 mol L(-1) HNO3 at 95 degrees C. The separated solutions were free from most matrix elements and were aspirated into the ICP-MS directly. The decontamination factor for 238U is more than 10(4). The instrumental detection limit for 237Np was 0.46 pg mL(-1), which corresponds to 1.2 x 10(-5) Bq mL(-1). The method is more rapid than traditional radiometric techniques. It is also considered to be more suitable for environmental monitoring than existing methods based on TOA.
authors.affiliation: Department of Radiochemistry, China Institute of Atomic Energy, Beijing. Yqji@163.net
authors.forename: Y Q
authors.initials: YQ
authors.lastname: Ji
authors.forename: J Y
authors.initials: JY
authors.lastname: Li
authors.forename: S G
authors.initials: SG
authors.lastname: Luo
authors.forename: T
authors.initials: T
authors.lastname: Wu
authors.forename: J L
authors.initials: JL
authors.lastname: Liu