Extraction Chromatographic Studies of Cerium(IV) with Carboxylic Acid (n-Capric Acid) and its Separation from Rare Earth Elements

Department of Chemistry, Visva-Bharati, Santiniketan-731 235

Manuscript received 11 March 1991, revised 24 June 1992, accepted 3 July 1992

Cerium(Iv) was extracted at pH 4.75-6.0 from ammonium acetate-acetic acid buffer on silica gel column impregnated with n-capric acid (a high molecular weight carboxylic acid). It was separated from bivaleat Mg, Mn, Co, Ni, Zn and Cd in binary mixture at pH 5.1 as they could not form acetate complex. Cerium(IV) was separated by process of selective elution from elements like Fe^llI, Zr^IV, Pd^II, La^III, Pr^III, Nd^III, Sm^III, Gd^III, Dy^III, Hg^ll, Pb^ll, Th^IV and U^VI by exploiting differences in stability of acetate complexes. Cerium(Iv) was separated from multicomponent mixture containing Zn^II, Zr^IV, Pb^ll, Th^IV, U^VI and rare earth elements by a process of selective sorbtion and selective elution. The proposed method is simple, rapid and selective.