Experimental Study of Lithium Extraction from a Lithium-Containing Geothermal Mud by Hydrochloric Acid Leaching

摘要

The present study focuses on the recovery of lithium from solid phases of a lithium-containing geothermal mud through hydrochloric acid leaching. The dried mud was initially characterized using different techniques, which includes particle size analyzer, X-ray diffraction, X-ray fluorescence, and atomic absorption spectrophotometer. The leaching experiments were carried out for 24 h with different variables and at different levels of variables, which includes hydrochloric acid concentration (3 M, 4 M, 5 M, and 6 M), leaching temperature (60 degrees C, 70 degrees C, 80 degrees C, and 90 degrees C), and solid percentage (5%, 10%, 15%, and 20%). Taguchi method involving the use of orthogonal arrays was used in designing and reducing the required number of experimental conditions. A simple mathematical model was used to determine the optimum condition within the investigated conditions. Analysis of variance (ANOVA) was also used in determining the degree of significance of variables in influencing the lithium recovery. The highest lithium recovery of 98.3% was obtained at the leaching experiment with hydrochloric acid concentration of 6 M, leaching temperature of 90 degrees C, and solid percentage of 10%. The results of this study provide new information and insight about the possibility of the lithium extraction process from the geothermal mud which has been so far considered as waste.