Determination of Optimum Conditions for the Separation of Zirconium and Hafnium

Zirconium and hafnium are the two most important elements in the nuclear industries. Zirconium is used in fuel rods due to its low neutron absorption cross section. On the contrary, hafnium has a very high neutron absorption cross section, therefore it must be separated from zirconium. The extractive separation of zirconium and hafnium have been investigated using Taguchi method. The separartion parameters were acid type (Sulfuric, Nitric, Hydrochloric) and their concentrations (10-2, 1, 5M) and extractant type (D2EHPA, Cyanex 301, Cyanex 302). The optimum conditions were determined as 5M nitric acid in addition with 5×10-3 M Cyanex 302 in the kerosene. Under these conditions, the zirconium the extraction percent and the separation factor were 99.5% and 8.7, respectively. For detailed investigation from the achieved results by Taguchi method, the effects of different parameters such as agitation time, nitric acid concentration, extractant concentration, sodium nitrate concentration and diluent type were considered.