| Popis: |
Atomic Minerals Division, Department of Atomic, Energy, R. R. Puram, New Delhi-110 066 Indian Institute of Technology, New Delhi-110 029 Manuscript ,received 3 February 1989, accepted 4 May 1989 The mechanism of the extraction of europium(III) and neodymium(III) from aqueous buffer media with 4(p)-nitrobenzoy1-2,4-dihydro-5-methy1-2- pheny1-3H-pyrazol-3-one (NMPP) in toluene has been investigated. The value of log Kex. (where Kex. refers to the equilibrium M2++ 3HL\(\rightleftharpoons\)ML2+ 3H+) is —1.4 and —1.6 for Eu and Nd respectively. NMPP seems to be superior to the corresponding 4-benzoy1-2,4-d ihydro-5-methy1-2-phenyl-3H- pyrazol-3- one and also better than thenoyltrifluoroacetone and hexafluoroacetylacetone. The effect of various types of Lewis bases in combination with NMPP on the extraction of EuIIIand NdIIIhas also been studied. A large synergistic enhancement was observed in both the cases with all the Lewis bases. Synergistic extraction constants, stability constants and the stoichiometry of the respective adducts formed during the extraction have been calculated. |
