LAUSR

Abstract Shale gas produced water has a large number of inorganic compounds, originating from the shale layer and the fracturing fluid. Especially, the Marcellus shale gas produced water contains a relatively high concentration of lithium, one of the important metals in various industries; as a result, there have been several studies on recovering lithium from the produced water. However, the fluid also includes organic compounds, but their probable inhibitory effect on the recovery of profitable metal has not been thoroughly examined. In this study, solvent extraction was implemented to recover lithium from the produced water, containing different types and concentrations of alkanes in two consecutive stages. The first and second stage involved the removal of the divalent ions in the produced water, as well as the extraction of Li+ ions, respectively. During the extraction process, there was an inhibitory influence of organic compounds, with their effects on the Li recovery efficiency predominantly observed in the first stage vs. the second stage. Final lithium recovery efficiency after two extraction stages decreased with increasing alkane chain length and increasing concentrations of n-hexane.