Concentration and Recovery of Terbium from Waste Material by Use of Chelating Resin Functionalized with Diethylentriamine-Polyacetic Acids

Terbium contained in the industrial waste sample was recovered by use of the chelating resin functionalized with diethylentriamine-polyacetic acids type ligand (CMA resin) . 2 mole dm-3 HCl solution made almost perfect dissolution of terbium from the waste sample. The chelating resin column was applied to separate terbium from the leaching solution at pH 3.5: The sample solution was passed through the colomn and then the retained metals were released from the colomn by elution with 0.2 mol dm-3 HCl. Terbium (III) was concentrated from 0.1 wt% to 70.3 wt% by the column operation, but the separation of terbium (III) from Co (II) and Fe (II) was not successful due to the mutual similarity of the distribution coefficients. Oxalic acid was added to the eluate and pH of the solution was adjusted to modulate the oxalic ion concentration. Terbium oxalate free from Co (II) and Fe (II) could be precipitated. Upon calcination of the oxalate, terbium oxide was recovered as 99.7% purity.