Extraction of trivalent actinides and lanthanides by carbamoylmethylphosphonates

Seven carbamoylmethylphosphonates (CMP's), (RO)2P(O)CH2C(O) x NR'2, have been studied under identical experimental conditions to determine the relative effects of size and structure of the extractant molecule on the extraction of americium from nitric acid. Those compounds with unbranched alkyl chains (R and R') appear to be superior extractants; however, they generally have higher aqueous phase distribution, which may make them less useful in actual application. Nitric acid extraction, europium loading, and the dependence of americium extraction on aqueous acid concentration and on extractant concentration are discussed for a selected CMP. (orig.)