EFFECTS OF STRUCTURE OF N,N-DISUBSTITUTED AMIDES ON THEIR EXTRACTION OF ACTINIDE AND ZIRCONIUM NITRATES AND OF NITRIC ACID

The effects of changes in the structure of 21 N,N-disubstituted amides on the extraction of actinide and zirconium nitrates and of nitric acid are given. Successive alkyl substitution on the a-carbon atom greatly decreases the extraction of quadrivalent actinides and of zirconium, but only moderately decreases the extraction of hexavalent actinides and nitric acid. The extraction mechanisms for the extraction of uranyl nitrate and nitric acid are very similar to the mechanisms of extraction by trialkyl phosphates and dialkyl alkylphosphonates. However, the extraction mechanisms for the quadrivalent species by amides appear to be quite different from the mechanisms with the phosphorus compounds. A connection between the stretching frequency of the carbonyl bond in the amides and their power as extractants is substantiated in a general and qualitative way, but an exception is noted.