Moshier R.W. Analytical Chemistry of Niobium and Tantalum

N.Y.: Pergamon Press, 1964. — 278 p. — (International Series of Monographs on Analytical Chemistry. Vol. 16).The analytical determination of niobium or tantalum, especially the estimation of either in the presence of the other, or of either in the presence of titanium, has been one of the most difficult problems of analytical chemistry.
The difficulty results largely from the fact that small quantities of these metals often behave differently when in the presence of larger amounts of the others.
Thus it has long been the experience that many promising methods for the separation of pure niobium and tantalum on a commercial scale have failed in the end because a residual small percentage of one or other metal ceased to behave in its own characteristic manner and adopted the properties of the major component.
Similarly, when titanium is also present in solution with niobium or tantalum, the quantitative precipitation of these metals may be affected.
During the last 25 years, however, the increasing interest in niobium and tantalum and the development of new discoveries and techniques, have resulted in the publication of a large number of new methods of analysis.
Solvent extraction methods, now used on a commercial scale for the separation of the pure metals, have proved to be of use for analytical purposes, as also have chromatographic methods, whilst the use of a variety of new organic complexing agents which give coloured products have enabled niobium and tantalum to be determined spectrophotographically.
All these methods of analysis and many others are described in this book.
After a brief review of the salient features of the chemical and physical properties of the metals and of their analytically interesting compounds, the author proceeds to discuss the methods of bringing the samples into solution, the separation of the metals by precipitation methods, and their gravimetric determination.
He then deals with separations by solvent extraction, by ion-exchange and by chromatography, and goes on to discuss colourimetric methods with hydrogen peroxide, with polyphenols, with thiocyanate and with other reagents, titrimetric methods, separation by chlorination and fractional distillation, polarography, X-ray diffraction and X-ray fluorescence methods, and the use of radio-isotopes and neutron activitation.
Several reviews of the analytical chemistry of niobium and tantalum have appeared in the last ten years, but none so comprehensive as this, which is encyclopedic in its coverage.
It is essentially a complete reference book, and a book for the expert, in that some selection from the many methods described is still necessary, but the experimental details are ample even for the average chemist.
A most valuable feature is the provision of appended ânotesâ at the foot of detailed descriptions of procedure; these are succinct appraisals of the methods, draw attention to special points in the light of experience and give evidence of first-hand knowledge on the part of the author.
To any laboratory concerned with the analysis of niobium or tantalum, in fact to any with even a passing interest in this field, this book can be recommended as well worth a place on their shelves.