Constantes de formation des complexes de stoechiometrie 1:1 et 1:2 ainsi que des complexes mixtes formes entre le plutonium(III) et divers acides amino-polyacetiques

Determination of the formation constants of 1:1, 1:2 and mixed complexes between plutonium(III) and various aminopolyacetic acids The complexation of plutonium(III) with various aminopolyacetic acids is investigated by potentiometric titration at 25°C and at a constant ionic strength of 1 (KC1). The formation constants of the 1:1 complexes are reported for NTA, HEDTA, EDTA, DCTA and DTPA. The formation constants of the 1:2 complexes with NTA, HEDTA and EDTA as well as those of the mixed complexes formed between Pu(HEDTA) or Pu(EDTA) and NTA, IMDA or glycine are also reported. Several pK values of the 1:1, 1:2 and mixed complexes have been determined. These results are discussed within the framework of those obtained previously with the lanthanides.