Oxidation of americium in acidic solution

Abstract

A process is for oxidizing americium(III) to americium(VI) includes providing a aqueous acidic composition comprising americium(III) and a mineral acid and exposing the composition to ozone and silver ion under conditions suitable for oxidation of the americium(III) to americium(VI). Nitric, acid is a suitable mineral acid for the process. Extraction of the americium from the silver is possible using organic phosphonate extractant.

What is claimed is: 
     
         1 . A process for oxidizing americium(III) to americium(IV), comprising
 providing a aqueous acidic mixture comprising americium(III) and a mineral acid, and   exposing the mixture to a combination of ozone and metal ions selected from silver ions, cobalt ions, cerium ions, or a combination of the metal ions, under conditions suitable for oxidation of americium(III) into americium(VI).   
     
     
         2 . The process of  claim 1 , wherein the mineral acid is selected from nitric acid, hydrochloric acid, perchloric acid, phosphoric acid, sulfuric, or a combination thereof. 
     
     
         3 . The process of  claim 1 , wherein the aqueous acidic mixture comprises a trivalent lanthanide. 
     
     
         4 . An aqueous composition comprising a homogeneous mixture of americium, ozone, nitric acid and one of either silver ions or cobalt ions. 
     
     
         5 . The composition of  claim 4 , wherein the silver ions comprises silver(I). 
     
     
         6 . The composition of  claim 4 , wherein the silver ions comprises silver(II). 
     
     
         7 . The composition of  claim 4 , wherein the silver ions comprise silver(III). 
     
     
         8 . The composition of  claim 4 , wherein the cobalt ions comprise cobalt(II). 
     
     
         10 . The composition of  claim 4 , wherein the cobalt ions comprise cobalt(III). 
     
     
         11 . A process for separating americium from a composition including at least one lanthanide, comprising:
 providing an aqueous acidic composition comprising americium(III) and at least one lanthanide,   exposing the aqueous acidic mixture to ozone and metal ions selected from silver ions, cobalt ions, and cerium ions, under conditions suitable for oxidizing the americium(III) to americium(VI), and   separating the americium(VI) from the at least one lanthanide and from said metal ions.