Yao, Jiaru; Sun, Nan; Zhang, Chunyao; Han, Xinru; Xue, Ning; Liu, Wei; He, Tao

CHEMICAL ENGINEERING JOURNAL

2025, ,

Yao, Jiaru; Sun, Nan; Zhang, Chunyao; Han, Xinru; Xue, Ning; Liu, Wei; He, Tao

Geothermal brine, a highly promising liquid resource for lithium, has attracted wide attention, but low Li+ concentration, complex impurity ions require robust efficient Li+ ion sieve absorbent with open porous structure. But conventional composite absorbent using hydrophilic materials suffer from deformation and weak strength and loss of sieves, as well as adsorption performance. This work reported a new type of glassy engineering polyethersulfone polymer as the binder for preparation of composite bead adsorbents (HTO-PES) based on titanium-based adsorbents (Li2TiO3, LTO and H2TiO3, HTO). We investigated the LTO loading and bead size for optimal performance. With an adsorption capacity of 19.8 mg/g, the optimized beads achieved 83 % of the capacity found for pure HTO powder (23.7 mg/g). Following 7 cycles in real geothermal brine, the HTO-PES bead adsorbent maintained its adsorption capacity, with Ti4+ dissolution loss remaining under 0.5 %. The adsorption behavior of the beads satisfied the Langmuir isotherm and the pseudo-second-order kinetic model. Furthermore, adsorption column was built to demonstrate the practical application of HTO-PES beads; the adsorption capacity and breakthrough curves were accurately modeled by the Thomas equation and conformed to Yoon-Nelson model. The findings demonstrated that HTO-PES composite bead adsorbents exhibit significant substantial prospects for extracting lithium from geothermal brines.