Recovery of lithium from brine with different degrees of mineralization by resorcinol/urea–formaldehyde foam-supported H2TiO3

With the development of new energy industry, the extraction of lithium from liquid minerals has attracted extensive attention. Herein, a novel phenolic resin-supported H2TiO3 foam (RF/UF-HTO) was developed for Li+ recovery from aqueous solutions. It was found that when the thermosetting phenolic resin was modified with urea and then foamed by petroleum ether with boiling points of 60 ∼ 90 °C under the assistance of 1.5% Tween 80 + 3% sodium dodecyl sulfate, the material presented a porous 3D network structure with a high specific surface area and porosity. The maximum adsorption capacity of the material reached 52.41 mg·g−1. The adsorption rate was controlled by the particle diffusion, and the adsorption was proven to be an endothermic process by the microcalorimetry. The material exhibited high adsorption performance for low-concentration Li+ in geothermal water with a low degree of mineralization. The adsorption capacity reached 21.50 mg·g−1 after only 6 h, and the attenuation of adsorption capacity was only 1.96 mg·g−1 after 10 cycles. Because of the high Mg2+ concentration and high degree of mineralization, the adsorption capacity for Li+ in salt lake brine was low. This problem was successfully solved by regeneration with Ba(OH)2, by which the adsorption capacity was enhanced from 0.54 to 20.72 mg·g−1. Even for the fixed-bed adsorption, the adsorption capacity still reached 8.5 mg·g−1. Based on these excellent properties, the material and method developed in this work can be used for Li+ recovery from brine with different degrees of mineralization and composition.