Abstract: Lithium ion-sieve λ-MnO2 was obtained from spinel type precursor LiMn2O4 treated with nitric acid，and LiMn2O4 was synthesized with LiOH·H2O and Mn3O4 as raw materials by solid state reaction.Saturated adsorption capacity，pH titration curve，and distribution coefficient of lithium ion-sieve were determined，and the effects of calcination time on lithium extraction ratio， manganese dissolving ratio，and adsorption property of lithium ion-sieve were discussed.Results showed that the lithium extraction ratio and the manganese dissolving ratio were 95% and 25%，respectively，after the first nitric acid treatment; For λ-MnO2，the saturated adsorption capacity of Li+ was 30.9 mg/g in a 0.1 mol/L NaOH and 10 mmol/L LiCl mixed solution，which reached 76.9% of its theoretical saturated adsorption capacity（40.2 mg/g）；the pH titration curve and distribution coefficient（for Li+，Na+，and K+） of lithium ion sieve showed that this lithium ion-sieve exhibited excellent selectivity for Li+.

Key words: lithium ion-sieve；solid state reaction；adsorption；LiMn2O4；&lambda, -MnO2