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1.
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. 相似文献
2.
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. 相似文献
3.
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.
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.相似文献
4.
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. 相似文献
5.
Thyagarajan S Shay DT Incarvito CD Rheingold AL Theopold KH 《Journal of the American Chemical Society》2003,125(15):4440-4441
Reaction of TpR,MeCo(I) dinitrogen complexes (R = iPr, tBu) with trimethylsilyl azide yields structurally characterized compounds that imply the formation of reactive intermediates of the type TpR,MeCo=NSiMe3. These cobalt imido species apparently abstract hydrogen from the 3-substituent of the Tp-ligand, leading to the formation of amido complexes accompanied by either Co-C bond formation (R = tBu) or C-C bond formation (R = iPr). 相似文献
6.
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 相似文献
7.
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.
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.相似文献
8.
Anuradha Mishra Malvika Bajpai Sunita Pal Monika Agrawal Sushant Pandey 《Colloid and polymer science》2006,285(2):161-168
The application of Tamarindus
indica seed mucilage (Tam), a food grade polysaccharide, and its acrylamide grafted copolymer as flocculants was assessed for the first time for removal of various types of dyes from model textile wastewater containing azo, basic, and reactive dyes. Acrylamide grafted T. indica mucilage (Tam-g-PAM) was obtained by ceric ion initiated polymerization technique. A series of contact time experiments were conducted to assess the system variables such as concentrations of mucilage and dyes and pH. These flocculants reduce the dye concentration by flocculation and settling. The grafted copolymer, Tam-g-PAM showed better results for dye removal. The optimal flocculant concentration, which was required to effect flocculation, was independent of dye concentration within the range examined. Both the flocculants performed better for removal of azo dyes than for reactive and basic dyes. 相似文献
9.
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. 相似文献
10.
Reaction of cis-[PtCl2(AsPh3)2] with excess sodium sulfide in benzene gave the triphenylarsine analogue of the well-known metalloligand [Pt2(μ-S)2(PPh3)4] as an orange solid.The compound was characterised by detailed mass spectrometry studies, and by conversion to various alkylated and metallated derivatives.The sulfide ligands in [Pt2(μ-S)2(AsPh3)4] are less basic than the triphenylphosphine analogue, and the complex gives a relatively weak [M+H]+ ion in the positive-ion electrospray (ESI) mass spectrum, compared with the phosphine analogue.Methylation of an equimolar mixture of [Pt2(μ-S)2(PPh3)4] and [Pt2(μ-S)2(AsPh3)4] with MeI gave the species [Pt2(μ-S)(μ-SMe)(AsPh3)4]+ and [Pt2(μ-SMe)2(PPh3)3I]+, indicating a reduced tendency for the sulfide of [Pt2(μ-S)(μ-SMe)(AsPh3)4]+ to undergo alkylation.The lability of the arsine ligands is confirmed by the reaction of an equimolar mixture of [Pt2(μ-S)2(PPh3)4] and [Pt2(μ-S)2(AsPh3)4] with n-butyl chloride, giving [Pt2(μ-S)(μ-SBu)(EPh3)4]+ (E = P, As), which with Me2SO4 gave a mixture of [Pt2(μ-SMe)(μ-SBu)(PPh3)4]2+ and [Pt2(μ-SMe)(μ-SBu)(AsPh3)3Cl]+.Reactivity towards 1,2-dichloroethane follows a similar pattern.The formation and ESI MS detection of mixed phosphine-arsine {Pt2S2} species of the type[Pt2(μ-S)2(AsPh3)n(PPh3)4−n] is also discussed. Coordination chemistry of [Pt2(μ-S)2(AsPh3)4] towards a range of metal-chloride substrates, forming sulfide-bridged trinuclear aggregates, has also been probed using ESI MS, and found to be similar to the phosphine analogue. The X-ray crystal structure of [Pt2(μ-S)2(AsPh3)4Pt(cod)](PF6)2 (cod = 1,5-cyclo-octadiene) has been determined for comparison with the (previously reported) triphenylphosphine analogue. ESI MS is a powerful tool in exploring the chemistry of this system; in some cases the derivatising agent p-bromobenzyl bromide is used to convert sparingly soluble and/or poorly ionising {Pt2S2} species into soluble, charged derivatives for MS analysis. 相似文献