Elution profiles of lanthanides with α‐hydroxyisobutyric acid by ion exchange chromatography using fine resin

Experiments were carried out using a strong acid cation exchange resin with a particle size of 75–150 μm, termed as “fine resin” in hydrogen ion form for the elution of individual lanthanides Sm, Eu, Gd, Tb, and Dy that are produced as fission products in the spent nuclear fuel and generated in the effluent during reprocessing of spent nuclear fuel. Batch experiments were carried out to study the effect of concentration of nitric acid on distribution coefficient. The distribution coefficient values for these individual lanthanides were determined in nitric acid medium in the concentration range of 0.01–4.0 N. Uptake of each individual lanthanide by resin was increased with increased nitric acid concentration from 0.01 to 0.5 N and remained similar from 0.5 to 1.0 N and decreased thereafter up to 4.0 N. Column experiments were also carried out using the same resin to study the parameters like pH of the eluent, flow rate, and resin bed height under isocratic elution conditions for eluting lanthanide elements using α‐hydroxyisobutyric acid as eluent. The results of this study have indicated the possibility for the elution of individual lanthanides.     

Gravimetric and spectrophotometric determination of palladium with 2-hydroxy-5-methylpropiophenone oxime

2-hydroxy-5-methylpropiophenone oxime (HMP) reacts with palladium in strongly acidic media to form a yellow water-insoluble complex. Palladium has been determined gravimetrically and interference by certain ions studied. The yellow complex is extractable into carbon tetrachloride in the pH range 1-4. The absorption maximum of the complex lies at 375 mmu, and Beer's law is obeyed in the range 0-15 ppm of palladium. The sensitivity is 0.22 mug Pd/cm(2) for log I(0)/I = 0.001. The effect of a number of foreign ions has been studied and several can be tolerated to an appreciable extent. The ratio of metal: ligand in the complex is 1:2.     

Spectrophotometric determination of ruthenium with diphenylthiovioluric acid

Diphenylthiovioluric acid (DPHTVA) reacts with ruthenium(III) to form a complex which has an absorbance maximum at 520 nm. Effects of pH, heating time, buffer and reagent have been studied. DPHTVA has been found to be a sensitive reagent for ruthenium(III) (sensitivity = 0.0044 μg Ru/cm² for log I₀/I = 0.001), and has been made selective by the use of masking agents. The composition of the complex as revealed by different methods is 1:2 (ruthenium:DPHTVA).     

Spectrophotometric determination of zirconium using robinetin

Summary The complex formation between zirconium and robinetin has been spectrophotometrically investigated and made use of in the determination of zirconium. The complex has been found to contain zirconium and the flavonol in the molar ratio of 12. It obeys Beer's law up to 3.0 ppm of Zr and its stability constant has been calculated to be l.5×10⁹. The reaction is quite sensitive and selective at high concentrations of hydrochloric acid (sensitivity 0.0045 g/cm²).

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Zusammenfassung Zur spektrophotometrischen Bestimmung von Zirkonium wird als Reagens Robinetin empfohlen, das mit Zr einen Komplex im Verhältnis 12 (ZrRobinetin) bildet. Die Stabilitätskonstante wurde zu 1,5 · 10⁹ bestimmt. Das Beersche Gesetz wird bis zu 3,0 ppm Zr befolgt. In stark Salzsauren Lösungen ist die Reaktion empfindlich und selektiv (Empfindlichkeit: 0,0045 g Zr/cm²).

     

Spectrophotometric determination of antimony with 3,5,7,4'-tetrahydroxyflavone (kaempferol)

A selective spectrophotometric method is described for determination of antimony with kaempferol. Microgram amounts of antimony can be determined by measurements at 420 run in 0.1M hydrochloric acid. The molar absorptivity is 1.09 x 10(4) at 420 nm and the optimum range for accurate determination is 1.9-7.8 ppm of antimony.     

Phenanthraquinone monothiosemicarbazone as indicator for chelatometric determinations

A new compound, phenanthraquinone monothiosemicarbazone, is satisfactorily used in the chelatometric determination of copper(II), zinc(II), cadmium(II), mercury(II) and nickel(II). The method is applied in the analysis of various alloys.     

Thermal Studies on Some Lanthanide Complexes

The new mixed ligand complexes with the formulae Zn(2-bipy)(ox), Zn(4-bipy)_1.5 (ox)H₂ O, Zn(2,4'-bipy)₂ (ox)2H₂ O, Cd(2-bipy)(ox)2H₂ O, Cd(4-bipy)₂ (ox) and Cd(2,4'-bipy)(ox)2H₂ O (2-bipy, 4-bipy, 2,4'-bipy=2,2'-, 4,4'- and 2,4'bipyridine, ox=oxalate) were prepared. The thermal decompositions of these compounds were studied by means of TG, DTG and DTA in air. During heating the complexes decompose via different intermediate products to ZnO and CdO. The Zn(II) complexes are thermally more stable than the corresponding Cd(II) complexes. The influence of nitrogen atom position in the bipyridine isomers and nature of central atom on the thermal behaviour of these complexes was discussed. This revised version was published online in August 2006 with corrections to the Cover Date.     

Spectrophotometric determination of cobalt with phenanthrenequinone monoxime

Phenanthrenequinone monoxime reacts with cobalt to form a yellow-orange insoluble 1:3 (cobalt:ligand) complex which is extractable into chloroform in the pH range 4.45-8.0. The determination of cobalt is carried out at 470 mmu. Beer's law is obeyed over the concentration range 0-3.0 ppm of cobalt. The sensitivity is 0-00336 mug of Co/cm(2) for 0.001 absorbance. The effect of a number of foreign ions has been studied.     

Studies onO-Vanillinoxime as an analytical reagent

o-Vanillinoxime has now been used for the gravimetric determination of copper and nickel alone and in presence of many foreign ions. Copper can be estimated in presence of appreciable amounts of cadmium, zinc, cobalt and lead. The interference due to iron (III), antimony (III), bismuth (III) and tin (II) can be removed by suitable masking agents. Determination of copper and nickel in presence of each other has also been carried out.