Polyethyleneimine Methylenecarboxylate : a macromolecular DTPA analogue for the plutonium ( IV ) chelation

The Th(IV) solution (from Th nitrate) used for each point of the complexation curves was protected with nitriloacetic acid (at ratio Th : NTA = 1 : 2) in order to avoid hydrolysis that occurs typically above pH 1–2 for actinides at oxidation state +IV. A quick check of Th speciation under these conditions using JChess simulation with BASSIST data base1 indicates that less than 10% of the initial Th is hydrolyzed.