RECOVERY OF EUROPIUM FROM A RARE-EARTH CHLORIDE SOLUTION

A two-stage Jones reductor column has been applied to the separation a nd purification of europium from a commercial rare earth chloride solu tion. The process consists of the reduction of Eu(III) to Eu(II) by a zinc amalgam, followed by the precipitation of europium(II) sulphate ( EuSO4) in an inert atmosphere (CO2). Variables such as acidity,,, conc entration and flow rate of the rare earth chloride solution in the Jon es column, mercury concentration in the zinc amalgam, concentration of the precipitating agent (sulphuric acid), and the inert gas flow rate , have been evaluated with a pure europium synthetic solution. Based o n the results, the experimental conditions have been adjusted to recov er europium from a commercial rare earth solution, containing 2.4 g l( -1) Eu2O3, 114.4 g l(-1) Sm2O3 and 64.2 g l(-1) Gd2O3 as the main cons tituents. The final product, assaying 99.4% Eu2O3, was obtained with a recovery of 92%. (C) 1998 Elsevier Science B,V. All rights reserved.