During recent years increased interest has been shown in the metal niobium. Because niobium has a high melting point (4376° F) and a low neutron cross-section, the Atomic Energy Commission has encouraged research on new methods of winning the metal from its ores with the ultimate hope of finding a process which would yield niobium metal at a reasonable price. The two areas of endeavor in which·the principal difficulties in finding such an economic process occur are the separation of tantalum from the niobium and the conversion of purified niobium salts to the metal. This report, then, was written to consolidate the more important information available in the literature on one of these troublesome areas, that of the separation of niobium and tantalum. It is to be noted, however, that all the references available in the literature on niobium-tantalum separation are not included in this report, but only those which appear to have the most usefulness for future endeavors on this problem.
Koerner, Ernest L. and Smutz, Morton, "Separation of niobium and tantalum - a literature survey" (1956). Ames Laboratory ISC Technical Reports. 145.