Akademik Veri Yönetim Sistemi
Physicochemical Problems of Mineral Processing, cilt.62, sa.1, 2026 (SCI-Expanded, Scopus)
In this study, following characterization, the leaching behaviour of scandium from a clayey laterite ore sample in sulfuric acid solutions under atmospheric pressure was investigated. The ore sample was characterized using various techniques and it was found to be a low-grade, predominantly smectite-containing nickel laterite ore with 71 ppm Sc and 6340 ppm Ni. Nickel in the ore sample is associated mainly with the clay (smectite/serpentine group) minerals, goethite and asbolane, while scandium is associated with goethite and silicate phases. Following characterization, the leaching behaviour of scandium, together with nickel, iron, magnesium, and aluminum, was determined under different experimental conditions (H2SO4 concentration: 0.1-4 M, leaching temperature: 20-90°C, leaching time: 2.5-240 minutes), and the leaching efficiencies of Sc, Ni, Fe, Mg, and Al found under the selected conditions (4 M H2SO4, 90°C, 60 min.) were 88.1%, 91.6%, 64.3%, 87.5%, and 66.2%, respectively. The leaching kinetics of scandium was determined to be controlled by a mixed mechanism with an activation energy of 23.2 kJ/mol. The preliminary scandium extraction experiments performed on the loaded solution obtained after leaching under selected conditions showed that 98.6% of scandium in the solution could be selectively separated against nickel and iron using an extractant containing 5% di(2-ethylhexyl) phosphoric acid (D2EHPA) in kerosene. The preliminary experiments also showed that scandium could also be selectively separated from the loaded solution and directly from the leach pulp by using an ion-exchange resin impregnated with D2EHPA.