Abstract: Manganese lithium ion sieve is suitable for extracting lithium from salt lakes with high magnesium lithium ratio in China. MnO₂·0.5H₂O lithium ion sieve were synthesized from three different manganese sources: MnSO₄， MnOOH and Mn₃O₄. The products were characterized by X-ray diffraction (XRD)，scanning electron microscope (SEM)， special surface area analysis (the BET method)， and atomic absorption spectrometer (AAS).The experimental results show that the three manganese sources can synthesize relatively pure Li_1.6Mn_1.6O₄ ion sieve precursors. After acid pickling， the BET specific surface areas of the three lithium ion sieves have increased significantly compared with the precursors， with increments of 546.6%， 129.9% and 142.2% respectively. Among them， the ion sieve synthesized by MnSO₄ has the largest specific surface area， and the ion sieve synthesized by Mn₃O₄ has a special rod shape. The adsorption results showed that the lithium adsorption capacity of the ion sieve synthesized by MnSO₄ source was the highest. In the low lithium solution with a concentration of only 20mg/L， the lithium extraction capacity was 19mg/g.

Key words: manganese source; lithium ion sieve; low temperature hydrothermal; adsorption performance; lithium extraction