Concentration of lithium by forward osmosis

As an applying potential for a part of production of lithium (Li) from salt lake brine, forward osmosis was investigated by using semi-permeable membranes, sodium chloride (NaCl) and magnesium chloride (MgCl2) as draw solutions under several operational conditions. Cellulose triacetate and thin-film composite membranes and their orientations were compared. The results indicated that concentration of Li was higher using the thin-film composite membrane with MgCl2 as the draw solution. The effect of pH was insignificant. The results also showed that water flux decreased with increasing Li concentration on the feed side. Internal concentration polarization played an important role when rejection of Li was higher in the active layer facing feed solution system. [Display omitted] •Investigation of an applying potential of forward osmosis for concentrating lithium from salt lake brine.•The pH of feed solution and salt concentration of draw solution affect the concentration efficiency of lithium.•Internal concentration polarization is important to water flux and lithium rejection by forward osmosis membrane.•Internal concentration polarization affects the orientation of membrane surface.