Selective adsorption of lithium ions from Urmia Lake onto aluminum hydroxide

Abstract

In the present study, recovery of lithium as lithium aluminate from Urmia Lake was investigated. A coprecipitation method was utilized by using an aluminum salt $\left( {{\text{AlCl}}_{3} .6{\text{H}}_{2} {\text{O}}} \right)$. Lithium ions are adsorbed on aluminum hydroxide, which is prepared by adding NaOH and ${\text{AlCl}}_{3} .6{\text{H}}_{2} {\text{O}}$ to the brines at ${\raise0.7ex\hbox{${{\text{Al}}^{3 + } }$} \!\mathord{\left/ {\vphantom {{{\text{Al}}^{3 + } } {{\text{Li}}^{ + } }}}\right.\kern-0pt} \!\lower0.7ex\hbox{${{\text{Li}}^{ + } }$}}$molar ratio ≈5. The results showed that the maximum ${\text{Li}}^{ + }$ ion adsorption was adsorbed at pH ~ 7. Also, by increasing the temperature from 30 °C to 40 °C, lithium ions adsorption was decreased. The maximum adsorption amount of ${\text{Al}}\left( {\text{OH}} \right)3$ was at 30 °C, pH = 7 and density 1.31. The obtained results from adsorption of ${\text{Li}}^{ + }$ of Urmia Lake were compared with four isotherm models, Langmuir, Dubinin–Radushkevich, Freundlich and Temkin isotherms. In addition, sulfuric acid was used for ${\text{Li}}^{ + }$ desorption from aluminum hydroxide.