A facile strategy toward ion-imprinted hierarchical mesoporous material via dual-template method for simultaneous selective extraction of lithium and rubidium

作者：Xu, Xuechao; Li, Yang; Yang, Dongya; Zheng, Xudong; Wang, Yuanyuan; Pan, Jianming; Zhang, Tao; Xu, Jicheng; Qiu, Fengxian^*; Yan, Yongsheng^*; Li, Chunxiang

来源：Journal of Cleaner Production, 2018, 171: 264-274.

DOI：10.1016/j.jclepro.2017.10.023

• Mesoporous material
• Simultaneous adsorption
• Lithium
• Rubidium
• Ion imprinting technology

With the increasing market demands of lithium (Li) and rubidium (Rb) around the world, the shortage of Li and Rb seriously restrict the further development of relevant industries. In this work, we report a superior lithium/rubidium imprinted hierarchical porous silica (Li/Rb-IHPS) for the simultaneous selective extraction of lithium and rubidium from aqueous solution. Li/Rb-IHPS was prepared by ion imprinting technology (IIT) by using 12-crown-4 (12-C-4) and N-[(3-Trimethoxysilyl) propyl] ethylendiamine triacetic acid trisodium salt (TMS-EDTA) as functional monomers. The structure, thermal property and surface functional groups of as-prepared Li/Rb-IHPS material were characterized by Fourier infrared spectroscopy (FT-IR), elemental analysis, thermogravimetric analyzer (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and nitrogen adsorption-desorption. The results indicate that the as-prepared material has a hierarchical mesoporous structure (peak pore at ca. 3-4 nm and 12-15 nm) with high specific.surface area (BET) (242.47 m(2) g(-1)). The adsorption experiments show that Li/Rb-IHPS has a high adsorption capacity for Li+ (166 mu g g(-1)) and Rb+ (141 mu g g(-1)). The adsorption process can be described by pseudo-second-order kinetic model, suggesting that the adsorption for Li+ and Rb+ is controlled by chemical adsorption. And the Langmuir isotherm model can well fit the experimental data, illustrating that the adsorption process are all monolayer adsorption reactions. Additionally, the adsorption selectivity and reusability measurements were also investigated. Compared with some ions such as Na+, K+, Mg2+ and Cs+, Li/Rb-IHPS material shows excellent adsorption selectivity for Li+ and Rb+. After five cycles, the Li/Rb-IHPS material remains high adsorption capacity for Li+ (94%) and Rb+ (93%). The obtained results indicate that Li/Rb-IHPS can be used to extract the lithium and rubidium from oceans and lakes selectively, rapidly, and environmentally.

• 出版日期2018-1-10
• 单位江苏大学