PLUTONIUM IN CORAL SOIL DATE DRAFTED: 30 January 1978 DOE/ERSP PROCEDURENO.10 APPROVED: 15 February 1978 by Don R. Martin (ERSP Manager) Plutonium in Coral 1. Dissolve ashed residue with 30ml of 8N HNO3. Place in ultrasonic cleaner, if necessary, to dissolve sample. (HF treatment is necessary on all samples containing silicates.) Plutonium-236 is added as internal tracer. Add 5ml of 25% w/v NaNObo; place on hot plate for 5-10 minutes to expel NOg fumes. Cool sample at room temperature. Transfer to 125ml separatory funnel, add 40m1 of 30% v/v Aliquat-336 in xylene, shake for 5 minutes, allow phases to separate for 15 minutes. Save aqueous phase for americium analyses. Add 30 ml of 8N HNOg3to Aliquat-336, shake for two minutes, Allow phases to separate for five minutes and reserve aqueous phase for americium anaylsis. Back extract plutonium from Aliquat-336 with 50 ml of HClO, + oxalic acid solution. Shake for 5 minutes. Collect plutonium in 150 ml beaker. Add 1 ml of 5% NaHSO, and evaporate sample in perchloric fraction hood. Rinse the wall of beaker with HNOg and evaporate to incipient dryness. Dissolve sample in 75 m1 8N HNOg. Pass through an ion column containing AG1X8 (50-100 mesh) or AG1X2 (50-100 mesh) ion exchange resin previously treated with 50 ml of 8N HNOg3. After the sample has passed through the resin column,rinse column with 70 ml of 8N HNOs, follow with 80 ml of 9M HCl. 10. 11. Elute the plutonium into a 150 ml beaker with 3 x 20 ml of a solution of 9M HCl and 1M NHygI at a 20 to 1 ratio. Add 10 ml HNOg to the eluate, evaporate to near dryness and rinse sides of beaker with HNO3 and HCl, dropwise. 12. Add 50 ml 8N HNOsgand repeat steps 9-11 if visible residue remains. 13. Continue heating the sample to dryness, removing the beaker just before the last of the liquid 14, Convert the residue to the chloride form by adding 1 ml of concentrated HCl and evaporate to evaporates. dryness. 15. Electrodeposit the sample as follows: a Add 2 ml of 0.4N HCl to the beaker. Swirl. bd. Add 3 ml of 4% ammonium oxalate solution. Swirl. e. Transfer the electrolyte sample mixture into a numbered plating cell with deionized water. Add rinse to cell. Continue rinse and addition to cell until cell (1/8" from top) is full. Electrodeposit at 210 ma. A-10-1