Production of Lithium Hydroxide from Lake Brines through Electro–Electrodialysis with Bipolar Membranes (EEDBM)

To investigate the feasibility of a novel method to produce LiOH from lithium contained brine, A lab-scale electro–electrodialysis with bipolar membrane (EEDBM) was installed with an arrangement of bipolar membrane–cation exchange membrane–bipolar membrane–cation exchange membrane in series. Conventional electrodialysis (CED) stack configured with repeat-arranged five cation exchange membranes and four anion exchange membranes was installed as a pretreatment process. After preconcentrating and precipitating brine with CED and Na2CO3, a high purity of ca. 98% Li2CO3 powder was obtained. The influence of current density and feed concentration on the production of LiOH was investigated. EEDBM Process cost is estimated to 2.59 $/kg at current density of 30 mA/cm2 and feed concentration of 0.18 M. It can be inferred that lower energy consumption would be obtained at the case of scaling up. Considering the environmental aspects, the corporate process for LiOH production is also mutually beneficial.