Separation of individual rare earth metals is a very complicated process due to interferences from the highly abundant cerium with the adjacent light rare earth elements. In the present work, the separation of cerium was investigated by oxidation of cerium (III) using electrochemical generation of H2O2. Different factors were studied including concentration of oxidizing agent, solution pH, applied potential voltage and contact time. Comparisons between electrochemical generation of H2O2 and direct oxidation with H2O2 were made. In single element system, direct cerium oxidation demonstrated low oxidation percentage in the acidic media, especially at pH ranging from 1.5 to 3. Cerium oxidation was 2% at pH 1.5 and increased gradually to 50% at pH 3. In multielement systems, the electrochemical oxidation of Ce(III) reached 67% in highly acidic medium (pH 1.25). This means that electrochemical oxidation of Ce(III) is more effective than direct cerium oxidation especially in relatively high acidic medium. Moreover, the obtained results showed that electrochemical generation of H2O2 could be successfully applied rather than direct oxidation for separation of cerium from the other REEs with relatively high yield in the high acidic medium.
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