Homogeneous liquid-liquid extraction followed by X-ray fluorescence spectrometry of a microdroplet on filter-paper for the simultaneous determinationof small amounts of metals
S. Igarashi et al., Homogeneous liquid-liquid extraction followed by X-ray fluorescence spectrometry of a microdroplet on filter-paper for the simultaneous determinationof small amounts of metals, ANALYST, 125(5), 2000, pp. 797-798
Homogeneous liquid-liquid extraction with perfluorooctanate ion (PFOA(-)) w
as utilized for the preconcentration of certain types of metal chelates, su
ch as diethyldithiocarbamate, 1,10-phenanthroline and desferrioxamine B. Un
der the experimental conditions {i.e., [PFOA(-)](T) = 6.0 x 10(-3) mol l(-1
), [acetone](T) = 2.0 vol%, [HCl](T)=0.72 mol l(-1), room temperature}, the
maximum concentration factor was 500-fold. A method was then developed to
determine those metal chelates deposited in a microdroplet on filter-paper
using X-ray fluorescence spectrometry. As a result, when three types of che
lating agent were used together in the process, 15 metal ions [Ti(IV), Zr(I
V), V(V), Nb(V), Ta(V), W(VI), Fe(II), Co(II), Ni(II), Pd(II), Cu(II), Au(I
II), Hg(II), Bi(III) and Se(IV)] were simultaneously determined. The recove
ry of each metal was ca. 83-100%, except for W(VI) which was 60.2%. The cal
ibration curves for each metal ion were linear over the range from 5.0 x 10
(-7) to 1.0 x 10(-5) mol l(-1). The detection limits were at the 10(-8) mol
l(-1) level and the relative standard deviations were below 5%.