Lithium adsorption from brine by iron-doped titanium lithium ion sieves

Iron-doped lithium titanium oxides were prepared via a solid-state reaction and transformed into lithium ion sieves by acid treatment. Scanning electron microscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy showed that Fe3+ was doped into the Ti-O lattice and Ti-Fe-O bonds were formed. Iron-doping improved lithium ion adsorption from brines. The saturated adsorption capacity of the iron-doped ion sieves in brine (Li+ 1.56 g/L, pH = 8.8) was 34.8 mg/g. Lithium ion adsorption fitted pseudo-second-order kinetic and Langmuir equations, indicating that lithium ion adsorption on iron doped lithium ion sieves was chemical and predominantly monolayer. In addition, the iron-doped ion sieves showed excellent selectivity for lithium ion and good recyclability. These iron-doped ion sieves therefore provide effective lithium adsorbents for practical applications. (C) 2018 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.