Abstract

Lithium brine processing using Membrane Distillation-Crystallization (MDCr) technology has proven as a plausible approach for high-quality water recovery and production of high-purity crystals. Nevertheless, the crystallization of other valuable minerals from lithium brines, such as potassium and magnesium in the sylvinite and bischofite stages, has not been evaluated to date. The present study assesses the effect of varying potassium and magnesium concentrations in brines on the performance of MDCr at laboratory-scale. The highest transmembrane water flux was obtained using a Response Surface Methodology and confirmed by experimental tests, reaching values up to 4.1 kg/m 2 h and 3.3 kg/m 2 h for the sylvinite and bischofite stages, respectively. The produced crystals were characterized in terms of size distribution and composition, confirming the presence of NaCl/KCl and K-carnallite in the sylvinite and bischofite stages, respectively.