The extraction of Zr(IV) by 2-thenoyltrifluoroacetone (TTA) in carbon tetrachloride from aqueous hydrochloric acid solutions
is a slow process. The addition of a neutral extractant, di-n-pentyl sulfoxide (DPSO) enhances considerably the rate as well
as the percentage of extraction. The species extracted appears to be ZrCl2(TTA)2·2 DPSO. An increase in temperature results in a further increase in the rate and percentage of extraction. Studies have also
been carried out on the extraction of the metal by mixtures of various neutral extractants. Thermodynamic parameters associated
with the formation of the synergistic adducts have been evaluated.
The relative extent of extraction of mercury with potassium salts of ethyl, propyl, butyl, pentyl and benzyl xanthates has been studied employing a sensitive and rapid substoichiometric radiochemical method. The effect of pH on the extractability of mercury xanthate complexes into chloroform was investigated. Buffer solutions of pH 12, 11, 10, 9 and 5.5 were found to be suitable media for the maximum extraction of mercury as ethyl, propyl, butyl, pentyl and benzyl xanthate complexes, respectively. The procedures developed were utilized for the determination of mercury content in standard solutions and geological water samples collected in eight parts of Chittoor district of Andhra Pradesh.
A rapid and sensitive substoichiometric radiochemical method has been developed for the determination of microgram amounts of antimony employing potassium ethylxanthate as a reagent and chloroform as an extractant from sulfuric acid medium. The effect of associated ions on the extraction was studied. The method developed was successfully applied to determine the antimony content in standard solutions and synthetic mixture with an average error ±2.07%
The comparative extractability of zinc with potassium salts of ethyl, propyl, butyl, pentyl, and benzyl xanthates from the pH range of 3.5–9.0 into chloroform has been studied, employing a sensitive and rapid substoichiometric radiochemical method. The extent of reproducibility was tested in each case. The effect of associated ions on the extraction was studied. The amount of zinc present in the standard solutions was determined employing each xanthate separately. The zinc content present in geological water samples in and around Tirupati was determined by the method developed and compared with the values obtained by Atomic Absorption Spectrophotometry.
A sensitive and rapid radiochemical method has been developed for the determination of microgram amounts of indium(III) based on the substoichiometric extraction of its 13 complex with potassium ethyl xanthate from pH 7 ammonia buffer into chloroform. 5–50 g of indium was determined with an average error of 1.56%. The effect of associated species on the extraction was studied.
An accurate and rapid radiochemical method has been developed for the determination of silver based on the substoichiometric extraction of its complex with potassium 3-phenylmethyldithiocarbazate into chloroform from pH 5.5 acetate buffer. Microgram amounts of silver could be determined with an average error of ±1.1% and the effect of diverse metal ions was critically examined. The method developed was applied to evaluate the silver content of photofilm washings.
Authors:R. Reddy, P. Reddy, G. Reddy, and B. Rangamannar
A rapid radiochemical method for the determination of thallium(III) has been developed based on the substoichiometric extraction of its 13 complex with sodium isopropyl xanthate into chloroform from pH 9 ammonia buffer. The effect of foreign ions on the extraction was also studied. 10 g amounts of thallium were determined with an average error of 1.9%. The method has been successfully applied for the determination of thallium content present in sphalarite ores collected from Jawar Mines, Rajasthan (India).
A rapid and sensitive substoichiometric radiochemical method has been developed for the comparative extraction and quantification of silver with potassium salts of ethyl, propyl, butyl, pentyl and benzyl xanthates from hydrochloric, nitric and sulfuric acid media into chloroform. The effect of 0.1–4M H+ ion concentration of the respective acid on the substoichiometric extraction of silver was critically studied. The efficiency of the method developed was tested by the determination of 10–100 g silver in standard solutions with an average percentage of error better than 2. The methods developed have been utilized to determine silver content in photofilm washing collected from various photostudios in Tirupati, India.
A radiochemical displacement method has been developed for the determination of 10 g amounts of iron and antimony. The effect of pH and various foreign ions on the displacement of tracer60Co from labeled Co-o-Hydroxybenzaldehyde isonicotinoyl hydrazone (BIH) complex in isoamyl alcohol by iron and antimony was studied.
Authors:B. Reddy, L. Reddy, A. Reddy, M. Reddy, S. Sujatha, T. Ramamohan, and A. Damodaran
Synergistic solvent extraction of Eu(III) and Tb(III) from thiocyanate solutions with mixtures of 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (EHPNA) and di-2-ethylhexylphosphoric acid (DEHPA) or tributyl phosphate (TBP) or trioctylphosphine oxide (TOPO) or triphenylphosphine oxide (TPhPO) in benzene has been studied. The mechanism of extraction can be explained by a simple chemically based model presented in this paper. The equilibrium constants of the mixed-ligand species of the various neutral donors have been determined by non-linear regression analysis.