Abstract
Metal chelate was equilibrated between 1cm3 of dodecane and 1cm3 of a water-methanol mixture in a shaking vessel at 25°C. After phase separation, a 10mm3 portion of each liquid phase was applied to high performance liquid chromatography. Partition coefficient (P) was determined simply as the ratio of the chromatographic peak areas measured at a mobile phase with the same solvent composition. The present method makes possible the accurate determination of P and the simultaneous determination of P for a mixture of two or more metal chelates. The P values of Cr(acac)3at XMeOH 0.40, 0.30 and 0.20, where XMeOH denotes mole fraction of methanol in the water-methanol mixture, are 3.28×10-2, 5.65×10-2and 1.00×10-1, respectively. Simultaneous determination of P of Cr(acac)3 and Pd(acac) 2 at XMeOH 0.30 was performed and Pvalues of 5.56×10-2 and 1.35 were obtained respectively. P values of mer- and fac-isomers of Cr(bzac)3 at XMeOH 0.60 were simultaneously determined as 7.38×10-1and 7.72×10-1respectively. The relative standard deviation of P values thus determined was less than 2% for most instances.
