Hydrolysis of niobium pentachloride solutions

This paper reports on hydrolysis of NbCl5 which is used to recover oxide values for use ceramic and metals production. Reaction of NbCl5 with water is rapid, exothermic and vigorous, yielding a gelatinous slurry. In contrast, dissolution of NbCl5 in 12 N HCl is endothermic, resulting in a clear yellow solution. Such solutions can be de-hydrochlorinated by controlled contact with air, to precipitate a tantalum-rich solids, depleting the liquid of its tantalum content. In this way, cheap, useful Nb-Ta partial separation is achieved based upon differential oxide-chloride stability. Nb2O5 with <200 ppm Ta/Nb has obtained from starting levels of 2000 ppm. Observation are made on the different types of hydrolysis