Tris(2-ethylhexyl)phosphate as an extractant for trivalent gallium, indium and thallium

A systematic study of solvent extraction behaviour of gallium(III), indium(III) and thallium(III) with tris(2-ethylhexyl)phosphate from salicylate media has been undertaken and a scheme for their separation is proposed. The optimum extraction conditions are evaluated and described. The method is applicable to the analysis of standard aluminium and aluminium alloys samples. The results obtained are reproducible and accurate.     

An extraction study of gallium, indium and thallium using TPASO as an extractant

A method is proposed for the extraction and individual separation of trivalent gallium, indium and thallium from salicylate media using triphenylarsine oxide dissolved in toluene as an extractant. The optimum extraction conditions are evaluated and described. The extracted metal ions are stripped and estimated spectrophotometrically following complexation with 4-(2-pyridylazo) resorcinol. A possible mechanism of the extraction is discussed. The method permits rapid and precise individual separation of gallium (III), indium (III) and thallium (III) and is applicable to the analysis of alloy samples.     

Synergetic extraction and spectrophotometric determination of iron (II) in steel

Summary A simple and rapid method is described for synergetic extraction and spectrophotometric determination of iron(II). The Fe(II)--furildioxime-pyridine complex extracted into chloroform has a characteristic pink color measurable at 570 nm. Iron is also separated from associated elements and the results of the analysis of synthetic mixtures and standard steel samples are reported.

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Zusammenfassung Eine einfache und rasche Methode zur Extraktion und Bestimmung von Eisen(II) wurde beschrieben. Der Komplex Fe(II)--Furildioxim-Pyridin wird mit Chloroform extrahiert. Seine charakteristische rosa Farbe ist bei 570 nm meßbar. Eisen läßt sich so auch von Begleitelementen trennen. Die Analysenergebnisse für synthetische Gemische und Standard-Stahlproben werden mitgeteilt.

     

Liquid-liquid extraction of tungsten(VI) with mesityl oxide application to an alloy steel

A new and simple method has been developed for the rapid extraction of tungsten(VI) with mesityl oxide. Quantitative extraction occurs from solutions 1M in hydrochloric acid and 12M in lithium chloride (as the salting-out agent) with 75% mesityl oxide in isobutyl methyl ketone. Tungsten is finally determined photometrically as the thiocyanate complex in the aqueous phase. Tungsten-(VI) can be extracted and determined satisfactorily in the presence of several elements. The method is shown to be applicable to an alloy steel.     

Liquid-liquid extraction and separation studies of yttrium

A simple selective method is presented for the solvent extraction of yttrium from salicylate media by using triphenylphosphine oxide. Yttrium is extracted quantitatively from 0.05 mol/l sodium salicylate solution at pH 4.5–5.0 using 1.8% triphenylphosphine oxide dissolved in toluene as an extractant and can be subsequently stripped using water and determined spectrophotometrically with Thoron-I. This precise and accurate method permits the separation of Y from Sc, Ti, V, Cr, Fe, Zr, Hf, Th and U from binary mixtures and multi-component systems. Received: 17 January 1995 / Accepted: 12 May 1995     

Liquid-liquid extraction and separation studies of uranium(vi)

Summary Separation of uranium(VI) from iron(III), molybdenum(VI), vanadium (V), bismuth(III), zirconium(IV) and thorium(IV) is achieved by liquid-liquid extraction with 4-methyl-3-pentene-2-one (mesityl oxide; MeO) from sodium salicylate media (0.1M, pH 6.0). The extracted species is UO₂(HO·C₆H₄COO)₂·2MeO. A procedure for separating 50g of uranium from mg amounts of the other metals is described.

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Flüssig-flüssig-Extraktion und Trennung von Uran(VI)

Zusammenfassung Die Trennung des U(VI) von Fe(III), Mo(VI), V(V), Bi(III), Zr(IV) und Th(IV) läßt sich durch Flüssig-flüssig-Extraktion mit 4-Methyl-3-penten-2-on] (Mesityloxid, MeO) aus 0,1M Natriumsalicylat bei pH 6,0 durchführen. Die extrahierte Verbindung ist UO₂(HO·C₆H₄COO)2·2MeO. Ein Verfahren zur Abtrennung von 50g Uran von Milligrammengen der anderen Metalle wurde beschrieben.

     

Spectrophotometric determination of uranium(VI) using a synergic mixture of ethyl acetoacetate and pyridine

A method is proposed for the extractive spectrophotometric determination of uranium(VI) using the synergic combination of ethyl acetoacetate (EAA) and pyridine (Py) as extractants. The optimum conditions have been evaluated by varying pH and ethyl acetoacetate and pyridine concentration. The nature of the extracted species has been determined by 1g D-1g C plots and the extracted species was found to be UO₂(EAA)₂.Py. The method has been applied for the separation and determination of uranium(VI) from synthetic mixtures.     

Extraction and separation of scandium salicylate with triphenylphosphine oxide

Scandium can be extracted from 5.0 × 10^–2 mol/l sodium salicylate solution, adjusted to pH 4.0–5.0 with 0.5% triphenylphosphine oxide dissolved in toluene as an extractant. After stripping from the organic phase with 0.5 mol/l HCl it can be subsequently determined spectrophotometrically with Alizarin Red S. The method permits a separation of Sc(III) from Ti(IV), V(V), Cr(VI), Fe(III), Y(III), La(III), Ce(III), Nd(III) and Sm(III) in synthetic mixtures. The method is fast, simple and selective. Received: 6 May 1996 / Revised: 21 July 1996 / Accepted: 25 July 1996     

Performance of immobilized Saccharomyces cerevisiae in the removal of long lived radionuclides from aqueous nitrate solutions

The efficiency of tailor made immobilized Saccharomyces cerevisiae(biomatrix) for the sorption of radionuclides ²³³U, ²³⁹Pu, ²⁴¹Am, ¹³⁷Ce, ¹⁴⁴Cs, ^103,106Ru and ⁹⁰Sr from aqueous nitrate solutions at different pH was studied. Effect of ionic strength, anionic components, initial metal concentration and particle size of the biomatrix on the sorption of metal ions were investigated. At pH in the range of 1 to 2 more than 95% sorption of U, Pu, Am and Ce could be accomplished, while that of Ru was 65%. Sorption of Cs and Sr were negligible under similar conditions. The metal ion-biomatrix system for Pu, Am and Ce reached equilibrium within 60 minutes. In the case of U, equilibrium attained in 100 minutes. The presence of anionic components, Cl^-, C₂O₄ ^2-, CH₃COO^-, NO₃ ^- and SO₄ ^2- (up to 0.5 mol^.dm^-3 of their individual concentration) in the aqueous solutions has no effect on the sorption of Pu by the biomatrix. Sorption of U, Pu, Am were observed in the presence of several cationic impurities such as Al, Be, Cd, Cr, Fe, Mn, Pb, Ce, Dy, Eu, Gd and Sm. Metal sorbed on the biomatrix could be leached out using 5 mol^.dm^-3 nitric acid. The I.R spectra of U bearing biomatrix suggest chemical interaction of uranyl ion with the biomatrix.     

Extraction study of uranium(VI) and thorium(IV) salicylates with triphenylarsine oxide

Triphenylarsine oxide is proposed as an extractant for the solvent extraction of uranium and thorium salicylates. The optimum extraction conditions are established by studying the various parameters such as pH, sodium salicylate concentration, triphenylarsine oxide concentration, diluents and shaking time. The probable extracted species as ascertained by logD-logC plots are UO₂(Hsal)₂·2TPAsO and Th(Hsal)₄·2TPAsO. The method is simple, fast, precise and permits the determination of uranium and thorium in monazite sand samples.