Extraction of Lithium from Single-Crystalline Lithium Manganese Oxide Nanotubes Using Ammonium Peroxodisulfate

Kaiyuan Shi; Mingwu Luo; Jie Ying; Shunying Zhen; Zhenyu Xing; Ri Chen

doi:10.1016/j.isci.2020.101768

Extraction of Lithium from Single-Crystalline Lithium Manganese Oxide Nanotubes Using Ammonium Peroxodisulfate

iScience. 2020 Nov 4;23(11):101768. doi: 10.1016/j.isci.2020.101768. eCollection 2020 Nov 20.

Authors

Kaiyuan Shi¹, Mingwu Luo¹, Jie Ying², Shunying Zhen³, Zhenyu Xing³, Ri Chen^{4

5}

Affiliations

¹ School of Materials Science and Engineering, Sun Yat-Sen University, Guangzhou, Guangdong 510275, China.
² School of Chemical Engineering and Technology, Sun Yat-Sen University, Zhuhai, Guangdong 519082, China.
³ School of Chemistry, South China Normal University, Guangzhou, Guangdong 510006, China.
⁴ School of Electromechanical Engineering, Guangdong Polytechnic Normal University, Guangzhou, Guangdong 510635, China.
⁵ School of Electromechanical Engineering, Guangdong University of Technology, Guangzhou, Guangdong 510006, China.

Abstract

In this work, a spinel single-crystalline Li_1.1Mn_1.9O₄ has been successfully synthesized using β-MnO₂ nanotubes as the self-sacrifice template. The tubular morphology was retained through solid-state reactions, attributed to a minimal structural reorganization from tetragonal β-MnO₂ to spinel Li_1.1Mn_1.9O₄. The materials were investigated as sorbents for lithium recovery from LiCl solutions, recycled using H₂SO₄ and (NH₄)₂S₂O₈. Li_1.1Mn_1.9O₄ nanotubes exhibited favorable lithium extraction behavior due to tubular nanostructure, single-crystalline nature, and high crystallinity. (NH₄)₂S₂O₈ eluent ensures the structural stability of Li_1.1Mn_1.9O₄ nanotube, registering a Li⁺ adsorption capacity of 39.21 mg g^-1 (∼89.73% of the theoretical capacity) with only 0.08% manganese dissolution after eight adsorption/desorption cycles, compared to that of 1.21% for H₂SO₄. It reveals the degradation of sorbent involves with the volume change, Mn reduction, and Li/Mn ratio depletion. New strategies, based on nanotube adsorbent and (NH₄)₂S₂O₈ eluent, can extract lithium ions at satisfactorily high degrees while effectively minimizing manganese dissolution.

Keywords: Chemical Engineering; Materials Chemistry; Materials Science.