Spectrophotometric estimation of rhenium with 5-chloro-2-hydroxythiobenzhydrazide after its extraction separation using n-octylaniline.
A solution of n-octylaniline in chloroform extracts rhenium selectively from 0.12-0.16 M nitric acid medium. Rhenium from the organic phase is backstripped with 5% aqueous ammonia solution and estimated spectrophotometrically with 5-chloro-2-hydroxythiobenzhydrazide (5-Cl-2-OHTBH). 5-Cl-2-OHTBH forms a blue complex with rhenium on heating in the acidity range 0.40-3.5 M HCl. The complex is extracted into chloroform and its absorbance is measured at 580 nm. The complex is stable for more than 12 h with a molar extinction coefficient of 9.0 x 10(3)l mole(-1) cm(-1) and a Sandell sensitivity of 0.019 mug cm(2).
Sawant
S S
SS
Anuse
M A
MA
Chavan
M B
MB