Rapid determination of environmental plutonium in large water samples by means of manganese dioxide Co-precipitation and extraction chromatographic separation

Plutonium activity determinations in environmental water samples are routinely performed in many laboratories. Due to the low plutonium concentrations and the complexity of the plutonium aqueous chemistry, these analysis involve cumbersome preconcentration and separation procedures and long measurement times. We describe a procedure where MnO2(s) is used as scavenger to preconcentrate Pu prior to separation by the transuranium specific extraction chromatographic resin TRU-Resin. The ability of MnO4-/MnO2(s) to destroy organic matter and oxidise plutonium is combined with the specific behaviour of the TRU-resin for transuranium elements. The method facilitates a rapid preconcentration and separation of plutonium. With the use of this procedure, the laboratory work on one sample can be performed in one day with minimum attention. The overall yields from a 200 litre fresh- or seawater sample to a measurable Pu source are between 70-85%. (orig.)