STUDY OF LITHIUM EXTRACTION FROM SIDOARJO GEOTHERMAL MUD BY LEACHING IN HYDROCHLORIC ACID

• Main Author: Farras Madisaw, Rafi
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/49096
• Institution: Institut Teknologi Bandung

The hot mud flooding in Sidoarjo was a disaster that occurred 13 years ago in the Sub-District of Porong, Sidoarjo Regency which resulted in inundation of the surrounding residential area. Until now, mudflow still occurs and there is no significant utilization yet of the Sidoarjo mud except partly for building materials. Investigation results of researchers from Japan and USA showed that the Sidoarjo Mud (next is abbreviated by Lusi), which is a geothermal mud, actually has a valuable metal content, one of which is lithium metal which can be extracted and used as raw material for batteries. Not many researchers have analyzed the content of Lusi and studied the process of lithium extraction from Lusi. In this research work, Lusi was characterized and the effectiveness of the lithium extraction process from Lusi by leaching in hydrochloric acid solution was studied. The research activity began with preparation of Lusi sample received from PT. Lapindo Brantas which includes of drying, homogenization and sampling. The sample was then analyzed by X-Ray Diffraction (XRD) to identify dominat minerals present on sample, X-Ray Fluorescence (XRF) to determine chemical composition of the Lusi sample and Particle Size Analyzer (PSA) to determine the particle size distribution of the sample. Before the leaching experiment was carried out, an experimental design was made by using L16 orthogonal array (43). The leaching experiments were carried out for 24 hours using dried Lusi sample under variations of HCl concentration, leaching temperature and solid percentage. After obtaining the data of extraction percentage of lithium from the experiments, the data were analyzed using Taguchi and ANOVA methods to obtain the optimum conditions for leaching and the significance of the effect of the variables on the extraction percentage of lithium. In addition, lithium leaching selectivity to iron and aluminium was also investigated. The experimental results showed that the highest extraction percentage of lithium was 97.36%, which was obtained from the leaching experiment at HCl concentration of 5M, leaching temperature 90oC and solid percentage of 10%. The result of data processing by using Taguchi method showed that the optimum conditions for obtaining the highest extraction percentage of lithium were at HCl concentration of 6M, leaching temperature 90oC and solid percentage of 10%. The experiment conducted at this optimum condition, resulted in lithium extraction percentage of 98.32% and the lithium leaching selectivity against iron and aluminium of 0.56 and 0.60 respectively (scale 0-1). The result of data processing by using ANOVA showed that in the range of examined variables, the variables that affect the extraction percentage of lithium are leaching temperature, HCl concentration and solid percentage with contributions 66.1%, 12.2% and 11.2% respectively.