Highly Lithium Adsorption Capacities of H1.6Mn1.6O4 Ion‐Sieve by Ordered Array Structure

Spinel‐structured Li1.6Mn1.6O4 (LMO) has received wide attention as ion sieve for the recovery of lithium from aqueous lithium resources. In this work, the branched‐like LMO particles were prepared via calcinating orthorhombic LiMnO2. After extracting of Li+ in hydrochloric acid, the branched‐like H1.6Mn1.6O4 (HMO) was obtained. During the preparing process, the structure, morphologies of LMO and HMO were characterized by XRD and SEM. The results indicated that HMO maintained the spinel and ordered array structure, which was beneficial to the lithium uptake behavior. Compared to normal HMO nanoparticles, the Li+ adsorption capacity of HMO by order array branched‐like structure can reach to 43.8 mg/g while rod‐like was 35 mg/g (CLi: 150 mg/L, pH 11, T: 25°C). The adsorption behaviors were well simulated by the pseudo‐second‐order and the Langmuir models. The reusability of the HMO implies that the branched‐like HMO is a potential adsorbent for Li+ recovery from aqueous lithium resources. A branched‐like H1.6Mn1.6O4 (HMO) ion sieve by ordered array structure was synthesized using branched‐like γ‐MnOOH as manganese source. This structure modification on H1.6Mn1.6O4 ion sieve not only increased the adsorption capacity of lithium, but also improved the chemical stability of adsorbent. These results showed that the HMO with ordered array structure is a promising candidate as an environmentally friendly Li+ adsorbent for successful application to liquid lithium resources.