EXTRACTION OF URANIUM(VI) AND VANADIUM(V) WITH 4-ADIPOYL AND 4-SEBACOYL DERIVATIVES OF BIS(1-PHENYL 3-METHYL-PYRAZOLONE-5) AND EFFECT OF DECANOL ON THE DISTRIBUTION BEHAVIOR OF THESE METAL-IONS

The liquid-liquid extraction of U(VI) and V(V) with 4-adipoylbis(1-phe nyl-3-methyl-pyrazolone-5) (H(2)AdP) and 4-sebacoylbis(1-phenyl-3-meth yl-pyrazolone-5) (H2SP) was studied in the presence and absence of dec anol (DOH). The studies show that in the absence of DOH the extracted species were (UO2)(2)(AdP)(2), UO2(HSP)(2), VO2(HAdP) and VO2(HSP). Ad dition of DOH to the organic phase resulted in enhancement of the extr action of V(V) at high HCl concentrations but reduced the extraction o f U(VI) due to a change in extraction mechanism. Subsequently, ion-pai r complex species VO2(HAdP)(DOH2+)(2).2Cl(-) and VO2(HSP)(DOH2+)(2).2C l(-) were extracted. The extraction constants K-ex and pH(1/2) for the various extraction systems were determined and used for explaining th e various extraction mechanisms observed.