Tech Xplore July 7, 2020
Considerable quantities of the element lithium are deeply hidden in rock formations below the Upper Rhine Trench: dissolved in salty thermal water reservoirs. Chile, Argentina, and Australia account for more than 80 percent of global production. Researchers in Germany have developed an environmentally friendly process to extract lithium from the existing infrastructure of geothermal plants, through which up to two billion liters of thermal water flow every year. There can be up to 200 milligrams per liter. The process involves filtering out the lithium ions from the thermal water and concentrated until lithium can be precipitated as a salt. The process uses the existing infrastructure of geothermal plants, hardly any overburden is produced and the land consumption is minimal, since the thermal water is returned to the underground after use, and no harmful substances are released and geothermal electricity and heat production are not impaired. Lithium can be continuously extracted within hours in the thermal water cycle of the geothermal plant. The process offers the possibility of extracting other rare and valuable elements such as rubidium or cesium from the thermal water…read more.