The silica gel adsorption behaviour of zirconium, niobium, ruthenium and cerium in hydrochloric acid has been investigated
by batch and column techniques. A satisfactory radiochemical separation of zirconium and niobium from each other and from
other fission products has been achieved by a two column technique. The recommended procedure consists of sorption of all
the nuclides on a primary silica gel column. Fifteen per cent of95Nb, all of the zirconium and all of the other fission products are eluted first by washing with 5.5 M HCl. A second elution
with concentrated hydrochloric acid then recovers the95Nb (free from other products). The solution from the first elution after evaporation to 1 ml is then passed through another
silica gel column and successively washed with 0.5M HCl, 5.5M HCl and concentrated HCl to obtain three fractions—other fission
products—95Zr free from other products—95Nb free from other products, respectively.