Tail-end purification of americium from plutonium loading effluents using a mixture of octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide and tri-N-butyl phosphate

The tail-end purification of Am from Pu loading effluents in 7.5M HNO3 containing ∼160 mg 1-1 Am and ∼1.2 mg 1-1 Pu has been carried out. With 0.2M CMPO + 1.2M TBP in dodecane as the extractant and stripping by 0.04M HNO3 + 0.05M NaNO2, the Pu level is brought down to ∼31.2 νg 1-1. When the acidity was reduced to 4.2M HNO3, one contact with 20% TLA/dodecane and subsequent extraction by a mixture of CMPO and TBP and stripping with 0.04M HNO3 + 0.05M NaNO2 gave Am samples without any detectable amounts of Pu. The recovery of Am was ∼90% by the first procedure and ∼98% by the second one. (author) 12 refs.; 4 tabs