LITHIUM EXTRACTION FROM PLTP DIENG GEOTHERMAL BRINE WITH SOLVENT EXTRACTION METHOD USING DI-(2-ETHYLHEXYL)PHOSPHORIC ACID (D2EHPA) AND TRIBUTYL PHOSPHATE (TBP)

• Main Author: Mustika Suud, Esty
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/72747
• Institution: Institut Teknologi Bandung

Lithium is a metal used as a primary material for making batteries. With the increasing demand for batteries used in electric vehicles, the demand for lithium is increasing. Geothermal brine has the element lithium, and geothermal brine at the Dieng PLTP is known to have lithium concentrations of 77.31 – 99.4 mg/L. The use of solvent extraction methods to extract lithium from geothermal brine has never been done, especially in Indonesia. The purpose of this study was to determine the conditions that affect the performance of the solvent extraction method and how optimally lithium can be extracted from PLTP Dieng geothermal brine using the solvent extraction method, as well as the implications of the recovery factor for calculating lithium that can be extracted on an annual basis. The lithium extraction process began with a pre-treatment process in which dissolved SiO2 and divalent ions (Mg, Sr, Ba, and Ca) were first precipitated. Hence, the brine sample was clean from competitor ions. The Li extraction percentage from brine samples from a mixed of 3 wells, 4 wells, and HCE 4 wells were respectively 94%, 93%, and 94% at optimum conditions, namely with an extractant concentration of 60%, (v/v) dilution of the solution feed (aqueous) 50x, initial pH 10 and 4 stages of the extraction using D2EHPA. Calculating the potential for lithium extraction using the volumetric method, with the experimental recovery factor, yields a potential lithium recovery of 51.3 tonnes/year.