Lithium Separation from Geothermal Brine to Develop Critical Energy Resources Using High-Pressure Nanofiltration Technology: Characterization and Optimization

Abstract

There is a shift from internal combustion engines to electric vehicles (EVs), with the primary goal of reducing CO2 emissions from road transport. Battery technology is at the heart of this transition as it is vital to hybrid and fully electric vehicles’ performance, affordability, and reliability. However, it is not abundant in nature. Lithium has many uses, one of which is heat transfer applications; synthesized as an alloying agent for batteries, glass, and ceramics, it therefore has a high demand on the global market. Lithium can be attained by extraction from other natural resources in igneous rocks, in the waters of mineral springs, and geothermal brine. During the research, geothermal brine was used because, from the technological point of view, geothermal brine contains higher lithium content than other resources such as seawater. The nanofiltration separation process was operated using various solutions of pH 5, 7, and 10 at high pressures. The varying pressures are 11, 13, and 15 bar. The nanofiltration method was used as the separation process. High pressure of inert nitrogen gas was used to supply the driving force to separate lithium from other ions and elements in the sample. The research results supported the selected parameters where higher pressure and pH provided more significant lithium recovery but were limited by concentration polarization. The optimal operating conditions for lithium recovery in this research were obtained at a pH of 10 under a pressure of 15 bar, with the highest lithium recovery reaching more than 75%.

Comparison of the Mg2+-Li+ Separation of Different Nanofiltration Membranes

“…When the pH was lower than the isoelectric point, the surface of the membrane was positively charged, while it was negatively charged at a pH higher than the isoelectric point [38]. The characteristics of membrane surface charge were related to the dissociation of membrane surface groups and the adsorption of anions and cations (H + , OH − ) in solution [39]. Since the nanofiltration membrane had a polyamide functional layer, the residual carboxyl functional group on the surface of the membrane dissociated when in contact with The pH of the feed solution will affect the membrane surface charge, thereby affecting the Donnan repulsion and the dielectric repulsion effect [37].…”

Surfactant-Capped Silver-Doped Calcium Oxide Nanocomposite: Efficient Sorbents for Rapid Lithium Uptake and Recovery from Aqueous Media

“…To recover or extract lithium from different aqueous sources, several conventional technologies have been used, such as chemical precipitation [12], solvent extraction [13], ion exchange [14], nanofiltration [15], membrane technology [16], adsorption [17][18][19], reaction-coupled separation [20], etc. Among these investigated technologies for Li + recovery, adsorption seems to be a very ideal method from an economic viewpoint and in terms of environmental friendliness [21,22].…”

Recovery of Lithium from Oilfield Brines—Current Achievements and Future Perspectives: A Mini Review

“…The fullscale lithium mine in the Albemarle's Silver Peak site in Nevada's Clayton Valley, USA produces about 5000 tons of lithium per year [23]. Numerous laboratory studies confirm the suitability of various techniques to recover lithium from geothermal waters [24][25][26] and positive pilot results encourage full commercialization.…”