%A NIM.: 22106030031 Naiya Yuan Arlita %O Didik Krisdiyanto, S.Si., M.Sc. dan Ir. Moch. Setyadji, M.T. %T PENGARUH VARIASI pH DAN KONSENTRASI KALIUM PERMANGANAT (KMnO₄) TERHADAP EFEKTIVITAS PEMISAHAN SERIUM (Ce) DARI KONSENTRAT LOGAM TANAH JARANG HASIL OLAH MONASIT %X Cerium (Ce) is one of the rare earth elements that exhibits distinctive redox behavior between Ce³⁺ and Ce⁴⁺, making it suitable for selective separation through oxidation and precipitation processes. This study aims to optimize the oxidation process of cerium from rare earth hydroxide (REOH) concentrates and to compare the characteristics of cerium precipitates before and after oxidation treatment based on X-Ray Fluorescence (XRF), Fourier Transform Infrared Spectroscopy (FTIR), and X-Ray Diffraction (XRD) analyses. XRF analysis results indicate that the initial REOH concentrate contains 36.27% cerium, confirming cerium as the dominant element in the raw material. The oxidation process was conducted using potassium permanganate (KMnO₄) with variations in pH and oxidant dosage. The sample without oxidation treatment produced a cerium content of 32.148% with a recovery of 51%. In contrast, the oxidized samples showed a significant improvement, where the optimum condition was achieved at pH 2 with the addition of 1.25 g KMnO₄, resulting in the highest cerium content in the precipitate of 70.47%, accompanied by a decrease in impurity elements such as La and Nd and an increase in cerium recovery up to 94%. FTIR analysis shows that the non-oxidized sample is dominated by O–H stretching bands around 3400 cm⁻¹, whereas the oxidized sample exhibits a characteristic Ce–O vibration band in the range of 500–600 cm⁻¹ with higher intensity. XRD analysis reveals that the sample without oxidation treatment does not form a single crystalline phase but instead consists of two crystalline phases, namely Ce₂O₃ and a partial CeO₂ phase. This indicates that, under non- oxidizing conditions, cerium exists in a mixed oxidation state of Ce(III) and Ce(IV), likely due to partial oxidation by dissolved oxygen or air during the precipitation and drying processes. Conversely, the XRD pattern of the oxidized sample shows prominent diffraction peaks at 2θ values of approximately 28.5°, 33.1°, and 47.5°, corresponding to the (111), (200), and (220) crystal planes of CeO₂ with a cubic (fluorite) crystal structure. The dominance of the CeO₂ phase confirms that oxidation using KMnO₄ successfully converts reduced cerium species into thermodynamically more stable cerium(IV). %K Serium, CeO₂, Oksidasi, Recovery, KMnO₄ %D 2026 %I UIN SUNAN KALIJAGA YOGYAKARTA %L digilib75480