Analytical applications of infra-red spectroscopy : The behaviour of the oxinates of niobium, tantalum and associated elements

✍ Scribed by Robert J. Magee; Ian Martin

• Book ID: 104101290
• Publisher: Elsevier Science
• Year: 1963
• Tongue: English
• Weight: 404 KB
• Volume: 28
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/s0003-2670(00)87246-3

✦ Synopsis

Investigations

carried out on reduction systems for niobium and tantalum have shown1 that niobium can bc determined colorimctrically in the presence of tantalum, but that titanium and, to a lesser extent, vanadium and tungsten always cause trouble. To overcome this difficulty the possibilities of infra-red spectroscopy using the potassium bromide disc technique were investigated. This technique2J had proved to be very successful in problems of a similar nature in earlier work.

It appeared necessary to choose complexes of niobium which are readily formed, of known composition, and possessing an.oxygen bridge between metal and ligand. All these characteristics appeared to be satisfied by the S-hydroxyquinoline complexes of these metals, which were therefore chosen. The method developed is based on the precipitation of the metal oxinates. The filtered precipitate is dried, mixed and pressed with potassium bromide into a disc, and examined in the infra-red spectrophotometcr.