Preparation of High Purity Iron by Solvent Extraction

Preparation of Sulfur of High Purity

A mc thod is described for producing sulfur thaL conLains Ie. Lhan 1.3 X lO5 m ole [racLion of li q uid-solu ble, solid-insolubl e impuriLies as dcLermin ed by Lh e fr'eezing point depression . This corr e ponds t.o a purity of 99.999 mole p ercen t . Man y of Lhe impurities, including organic maLLcl', a r(' re moved by o,(ldaLion with s ulfuric and nitric ac ids. The nonvo lati le impuri ties ...

Determination of Iron Species by Combination of Solvent Assisted-Dispersive Solid Phase Extraction and Spectrophotometry

A simple, rapid and sensitive solvent assisted-dispersive solid phase extraction method was developed for the extraction of iron(II) prior to its spectrophotometric determination. The Fe(II) reacted with 2,4,6-tris(2-pyridyl)-1,3,5-triazine, neutralized with sodium dodecyl sulfate and extracted onto the fine particles of benzophenone which were formed upon rapid injection of a mixture of benzop...

Preparation of High Purity Mullite Ceramics

Preparation of Highly Pure Vanadyl Sulfate from Sulfate Solutions Containing Impurities of Iron and Aluminum by Solvent Extraction Using EHEHPA

The preparation of highly pure vanadyl sulfate from sulfate solutions containing impurities of iron and aluminumwas investigated by solvent extraction with 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester (EHEHPA) and tri-n-butyl phosphate (TBP) as the phase modifier. The extraction and stripping conditions of vanadium (IV) and its separation from iron and aluminum were optimized. Under the...

High-purity preparation of a large DNA dumbbell.

We report on the efficient biochemical synthesis of a large DNA dumbbell starting from a pair of short DNA hairpins with long single-stranded tails of arbitrary sequence. The DNA dumbbell is obtained by enzymatic ligation yielding a 94-bp duplex stem closed at both termini by single-stranded loops of 5 nt. Following ligation, all unligated precursors and monoligated by-products were multiply bi...