SEPARATION AND DETERMINATION OF TRACE AMOUNTS OF BARIUM AS ITS THENOYLTRIFLUOROACETONE COMPLEX WITH DIBENZO-18-CROWN-6 BY MEANS OF SYNERGISTIC EXTRACTION AND FLAME PHOTOMETRY
M. Billah et al., SEPARATION AND DETERMINATION OF TRACE AMOUNTS OF BARIUM AS ITS THENOYLTRIFLUOROACETONE COMPLEX WITH DIBENZO-18-CROWN-6 BY MEANS OF SYNERGISTIC EXTRACTION AND FLAME PHOTOMETRY, Fresenius' journal of analytical chemistry, 347(3-4), 1993, pp. 107-110
A new method for the separation and determination of trace amounts of
barium at the ppb-ppm level in water as its thenoyltrifluoroacetone (T
TA) complex with dibenzo-18-crown-6 (DB18C6) comprises synergistic ext
raction and back extraction combined with flame photometry. The effect
of various factors (solvent, size of crown ether, reagent concentrati
on, shaking time, preconcentration factor, foreign ions etc.) on the e
xtraction and back extraction of barium has been investigated. The bar
ium TTA chelate in o-dichlorobenzene forms stable adducts with DB18C6
[Ba(TTA)2 . nDB18C6, n = 1 approximately 2]; the stability constants (
betan) of the adducts determined by means of the curve fitting method
are log beta1 = 3.77 and log beta2 = 7.91. The content of barium in so
dium chloride and sodium nitrate of guaranteed reagent grade was found
to be 9.67 +/- 0.08 mug/g and 7.86 +/- 0.09 mug/g, respectively.