LITHIUM EXTRACTION FROM SPODUMENE MINERALS IN GRANITIC ROCK FROM SOUTH KALIMANTAN BY DECOMPOSITION USING POTTASSIUM SULPHATE AND LEACHING USING WATER AND HYDROCLORIC ACID

• Main Author: Suharyanto, Ariyo
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/40180
• Institution: Institut Teknologi Bandung

Lithium is a metal element in Group IA in the Periodic System of Elements (Alkali Group) with atomic number 3 and atomic mass of 6.9. Lithium is most frequently used for material on batteries. The use of lithium batteries is quite high, in which the highest use rate (i.e around 60%) is for mobilephone batteries. Lithium battery technology can be classified into 4 types, namely Lithium-Ion Batteries (both liquid electrolytes and solid electrolytes), Lithium Air Batteries that utilize oxygen from the air, Lithium Water Batteries that use water as an electrolyte and Super Capacitor which serves to store electrical energy. Lithium Water Batteries are not suitable for the application of electric vehicles (EV), while the other three are the types that can be used as energy sources in electric cars. Indonesia is one of the countries that have the potential of lithium resources in brine water, spodumene minerals and other minerals in granitic rocks. Spodumene is one of the main minerals containing lithium. Spodumene minerals in granitic rocks are usually found in the form of ?-type which is not reactive. Therefore, it is necessary to convert this un-reactive type of mineral into ?- spodumene which is more reative and soluble in water and acid. One of the decomposition processes of ?-spodumen to ?-spodumene is by roasitng the ore with potassium sulfate (K2SO4). In this study, extraction of lithium from spodumene mineral oruginally from South Kalimantan granitic rocks was performed by decomposition of spodumene mineral wiht kalium sulfate followed by water leaching and acid leaching. The ore sample was mixed with potassium sulfate with a mass ratio of ore/K2SO4 of 1: 1 at a muffle furnace under at temperature variations of 350°C, 450°C, 550°C, 600°C, 700°C, 800°C, 900°C and 1000°C for 20 minutes, 40 minutes and 60 minutes. After obtaining the ?- spodumene phase, series of water leaching and acid leaching were performed with variations in stirring speed, ratio of solids/liquids, HCl concentration, temperature and leaching time. The XRD analysis results showed that granitic rocks from South Kalimantan contain spodumene minerals (LiAlSi2O6). The major minerals found in the granitic rock from South Kalimantan are albite (NaAlSiO3O8) and quartz (SiO2). The decomposition experiment by roasting at a temperature of 700 ° C for 40 minutes with K2SO4 additive resulted in conversion of ?-spodumene to ?- spodumene. The water leaching experiment of decomposed spodumen resulted in the highest Li extraction percentage of 97.57%% at stirring speed 300 rpm, ratio of solid/liquid (gr/ml) 1:3, temperature 40° C and 40 minutes laching duration, in which the extraction percentages of other elements at this condition are Al 0.0014%, Si 21.14%, Fe 0.00089% and Mg 2.88%. Meanwhile, the leaching process of decomposed sample by using hydrochloric acid resulted in the highest Li extraction percentage of 98.79% at stirring speed 360 rpm, acid concentration of 1M, ratio of solid/liquid (gr/ml) 1: 3, temperature 40°C and 40 minutes leaching duration, in which the extraction percentages of other elements at this condition are Al 0.025%, Si 10.94%, Fe 25.94% and Mg 33.72%.