Stannic silicomolybdate was synthesized at pH 0.63 .The experimental parameters such as order of mixing, mixing volume ratio, pH, stirring time, drying temperature were established for the synthesis of the material. The ion exchange capacity of Ca 2+ was improved from 0.53 to 1.73 meq/g for this newly synthesized material. The reproducibility of the product formed was checked. The exchanger was characterized on the basis of chemical composition, thermal and chemical stability, FTIR, TGA, DSC, X-ray and SEM analysis. The scanning electron microscopy of the material shows a regular diamond shape morphology. The presence of uniform morphology also indicated the absence of impure phases. The X-ray diffraction study showed the amorphous nature. Distribution coefficient studies of the metal ions on this material were performed in solvents having different acid dissociation constants namely trichloroacetic acid, formic acid and acetic acid. The effect of dielectric constants of solvents was studied by using dimethylsulfoxide; formic acid, acetic acid and trichloroacetic acid. The effect of temperature on the distribution coefficient was explored. It was finally concluded that 45 °C appeared to be the most favorable temperature. Important quantitative separations of metal ions in ternary mixtures included Ni 2+ –Co 2+ –Pb 2+ , Cu 2+ –Cr 3+ –Pb 2+ , Cu 2+ –Fe 3+ –Pb 2+ , Th 4+ –Zr 4+ –Sn 4+ , Cr 3+ –Ni 2+ –Fe 3+ , Cu 2+ –Ni 2+ –Ag + and Fe 3+ –Zn 2+ –Al 3+ . The practical potential of stannic silicomolybdate was explored by separating Cu 2+ and Zn 2+ quantitatively in synthetic mixtures as well as in commercially available brass samples.

Synthesis, ion exchange properties and analytical applications of stannic silicomolybdate: Effect of temperature on distribution coefficients of metal ions

Present work describes the electrochemical sensing and determination of phenolic compound (Phloroglucinol) using non-ionic surfactant Octyl phenol ethoxylate modified carbon nanotube paste electrode (OPEMCNTPE) in PBS (0.1 mol, pH 6.0) by Voltammetric method. The developed electrode was characterized by field emission scanning electron microscope (FE-SEM) and cyclic voltammetric (CV) studies. The OPEMCNTPE shows an exceptional catalytic impact towards the electro-oxidation of Phloroglucinol (PL) in contrast to the bare carbon nanotube paste electrode (BCNTPE). The rise in the concentration of PL is directly proportional to PL anodic peak current in the linear working range 10–90 µmol with a small detection limit (LOD) 0.71 µmol. This method was utilized for the estimation of PL in the water and blood serum samples.

Optimized Voltammetric Experiment for the Determination of Phloroglucinol at Surfactant Modified Carbon Nanotube Paste Electrode

The development of a rapid analytical technique for the determination of the platinumgroup elements (PGE) and gold in geological samples is described. The technique is based on selective aqua regia acid leach followed by a selective extraction (using diphenylthiourea and 1,2-dichloroethane) to separate the PGE and Au as a group from concomitant matrix elements. Organic extracts and aqueous raffinates were analysed by graphite furnace atomic absorption spectrometry, for which a comprehensive assessment of matrix interference effects was undertaken. Direct analysis of the aqua regia acid leachates by inductively coupled plasma-mass spectrometry (ICP-MS) was also evaluated. A number of other techniques were used to evaluate recoveries following acid attack, including x-ray fluorescence spectrometry and instrumental neutron activation analysis of solid residues and beta-autoradiography of thin sections to characterise PGE mineral solubility.

The results of these investigations identified optimum conditions for aqua regia extraction (20 ml of normal (3: 1) aqua regia for a 10 g sample, stirring for two hours at room temperature) and that quantitative recoveries can be expected for Au and semiquantitative for Pd with lower, but variable recoveries for Pt, Rh, Ru and Os and very low recovery of Ir. The solvent extraction procedure was effective in selectively extracting Au and Rh but was not quantitative in the extraction of Pt, Pd and Ru, the extraction of which appeared to be influenced by the sample matrix.

Further studies on the solubility in aqua regia of individual PGE minerals indicated that the main control of aqua regia extraction efficiency was sample mineralogy. The aqua regia leach procedure was applied to a range of samples that had been independently analysed by NiS fire assay as well as appropriate reference materials. This extraction procedure, with direct analysis of leachates by ICP-MS, was also used as the primary technique for characterising the homogeneity of two new chromitite reference materials, CHR-Pt+ and CHR-Bkg.

Development of rapid techniques based on selective dissolution for the determination of the precious metals in geological samples

An exhaustive review focusing on types of stationary phases, mobile phases, detection reagents and techniques involved in the identification, separation, and determination of inorganic anions in va...

Thirty-Five Years of Thin-Layer Chromatography in the Analysis of Inorganic Anions

Electrochromatographic behaviour of some amino acids on hydrous zirconium (IV) oxide impregnated papers have been carried out. Five background electrolytes of different pH were used for these studies at fixed potential difference and time

Chromatographic Studies on Hydrous Oxides of Polyvalent Metals. II. Electrochromatographic Studies of Amino Acids on Hydrous Zirconium (IV) Oxide Papers: Separation of Acidic Amino Acids

The ion exchange potential of antimonic acid and silica gel ‘G’ has been explored in thin layer chromatographic studies for the separation of anions. Several important and difficult binary separations of anions have been achieved as a result of these studies. Io− 3-Bro− 3, I−-Io− 3, Io− 4-Io− 3, Io− 4-Po−- 4, Br−-Bro− 3, Aso−- 4-Cro−- 4, S2o−- 3-Po−- 4, CNS−-S2o−- 3, Io− 4-Cro−- 4, Bro− 3-Cro−- 4, Io− 3-Cr2o−- 7 and s2o3-Cro−- 4 etc. are separations of analytical interest. Besides, a rapid microgram determination of [Fe(CN)6]3− (1–10 μg) and Cr2o2- 7 (2–10 μg) ions have been made.

Effect of Silica Gel ‘G’ on the Ion Exchange Behaviour of Antimonic Acid Thin Layers in The Chromatographic Study of Anions in Some Aqueous Organic Acid Systems: Determination of Ferricyanide and Dichromate Ions

Thin layer chromatographic behaviour of thirty phenols on calcium sulphate has been studied in six organic solvents. On the basis of Rf values, several important binary, ternary and quaternary separations of phenols have also been achieved. A rapid, quantitative microgram separation of phloroglucinol and resorcinol from synthetic mixtures containing many phenols have been developed using chlorobenzene and chloroform respectively.

http://nopr.niscair.res.in/bitstream/123456789/30876/1/IJCT%205%286%29%20383-386.pdf

Thin layer chromatographic separation and identification of some phenols on calcium sulphate : Determination of phloroglucinol and resorcinol

Zirconium (IV) phosphoantimonate impregnated papers have been used to study the electrochromatographic behaviour of 29 metal ions in buffers of weak organic acids with their corresponding ammonium salts as background electrolytes at fixed voltage and time intervals. As a result of these investigations, the variation in the average mobility of metal ions with the ionisation constants of the organic acids used in buffers and other parameters such as atomic numbers and charge on the metal ions has been studied. On the basis of the differential mobilites of the metal ions, which depends on the ion exchange properties of Zr(IV) phosphoantimonate and the nature of the complexes formed with the electrolytes, some binary, ternary and quarternary separation have been achieved. Besides microgram separations (25 μg-100 μg) of Pt(TV) from Pt group and other metal ions have also been achieved.

Electrochromatography of Metal Ions on Zirconium(IV) Phosphoantimonate Papers: Quantitative Separation of Platinum(IV) from Platinum Group and Other Metal Ions

Ram P. S. Rajput

Papers

Effect of Silica Gel ‘G’ on the Ion Exchange Behaviour of Antimonic Acid Thin Layers in The Chromatographic Study of Anions in Some Aqueous Organic Acid Systems: Determination of Ferricyanide and Dichromate Ions

Thin layer chromatographic separation and identification of some phenols on calcium sulphate : Determination of phloroglucinol and resorcinol

Electrochromatography of Metal Ions on Zirconium(IV) Phosphoantimonate Papers: Quantitative Separation of Platinum(IV) from Platinum Group and Other Metal Ions