Fig. 6: The performance of LBC for different concentrates obtained through modelling.

The modelling conditions are R_T = 60%, R_C and recovery rate are selected from a parametric study to find the minimal \({\rm{SEC}}\). More details on the modelling are available in the Methods section. The LBC concentration profile that increases 150 ppt to 200 ppt is shown in the upper panels. The specific energy consumption \({\rm{SEC}}\) (lower panels) is shown. a Simulation for lithium iodide (LiI) aqueous brine with properties of S_T(25 °C) = − 2.5 × 10⁻³ K⁻¹ and D(25 °C) = 2 × 10⁻⁹ m² s⁻¹, as in ref. ²². b Simulation for potash (K₂SO₄) aqueous brine with properties of S_T(25 °C) = 3.61 × 10⁻³ K⁻¹, as in ref. ²⁶, and D(25 °C) = 1.35 × 10⁻⁹ m² s⁻¹, as in ref. ²⁵. c Simulation for sodium hydroxide (NaOH) aqueous concentrate with S_T(25 °C) = 10 × 10⁻³ K⁻¹ and D(25 °C) = 1.23 × 10⁻⁹ m² s⁻¹, as in refs. ^23,27. All Soret and mass diffusion coefficients are evaluated at 50 °C assuming they follow the same temperature dependence trend of the Soret and mass diffusion coefficients for aqueous NaCl³⁴. The yield flow rate per channel footprint area in the LBC is 0.32, 0.34 and 0.78 m³m⁻²day⁻¹ for LiI, K₂SO₄ and NaOH, respectively.