Extraction of trivalent actinides with some substituted pyrazolones and their synergistic mixtures with tri- n-octylphosphine oxide in chloroform

Abstract

Trivalent actinides, Am, Cm, Bk and Cf, have been extracted with 1-phenyl-3-methyl-4-benzoyl pyrazolone-5 (HPMBP) or 1-phenyl-3-methyl-4-(3:5-dinitrobenzoyl) pyrazolone-5 (HDMPP) in chloroform. With HPMBP, Am, Bk and Cf are extracted as the self-adduct species M(PMBP) 3· nHPMBP ( n = 1 or 2) whereas in all the other systems formation of a non-adduct chelate species has been observed. With tri- n-octylphosphine oxide (TOPO), as the neutral donor, the synergistic adduct species are M(A) 3· mTOPO, where m is 1 or 2 in the above systems. The equilibrium constants (β 1, β 2 and K 2) for the organic-phase synergistic reactions have been calculated. In Am(III)-different β-diketones-TOPO systems the equilibrium constants follow the order HPMBP < HDMPP < thenoyltrifluoroacetone < benzoyltrifluoroacetone.