Tantalum as a High-Temperature Container Material for Reduced Halides

TANTALUM AS A HIGH-TEMPERATURE CONTAINER MATERIAL FOR REDUCED HALIDES 

Submitted by JOHN D. CORBETT Checked by ARNDT SIMON t 

We have found tantalum to be especially suitable for synthetic reactions and equilibrations involving elements and their reduced halides which lie to the left of group V in the periodic table, namely the alkali metals and alkaline earth metals scandium, yttrium, and the lanthanides titanium, zirconium, hafnium, thorium, and uranium. Tantalum and niobium are also uniquely suitable containers for the syntheses of their own lowest halides, for example, Ta6Br14 3 and CsNb6In.4 Tantalum containers have been extensively employed for the synthesis of halides, but reduced compounds of some other nonmetals, some oxides, for example, perhaps can be handled as well. 

For equilibration of molten salts with metals or intermetallics which would normally reduce a Pyrex or silica container (e.g., Al, Na3Bi) as well as for syntheses of the higher-melting and reactive intermetallic phases such as NaSb.5 

As a condenser or container for sublimation or fusion of some halides, the rare earth metal triiodides, for example (these undergo serious metathetical reactions with glass at elevatedtemperatures to yield SiX4 and the corresponding oxide or silicate). This pertains especially to the liquid and gaseous halides.6 

Tantalum as a High-Temperature Container Material for Reduced Halides 

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