关键词: 离子筛, 锂离子, 吸附, 尖晶石

Abstract: Spinel-type precursor LiMn2O4 ion sieve was synthesized with LiOH·H2O and MnCO3 as raw materials via controlling reaction conditions of inorganic manganese adsorption material.The final spinel-type ion sieve with higher Li+ selective adsorption property was prepared and further modified by acid treatment to extract lithium ions completely.Inorganic manganese adsorption materials were characterized by XRD，SEM，and BET，and adsorption capacities of ion sieve to lithium in pure lithium solution and brine were determined.Results showed that the precursors were closed to pure spinel-type crystals and had high specific surface area when the amount-of-substance ratio of lithium to manganese was 0.5 and reaction was at 800 ℃ for 15 h.The adsorption experiment showed that the ion-sieve could adsorb Li+ in alkaline solution and the exchange capacity of the ion-sieve was enhanced with the increasing of pH and temperature， its maximum capacity reached 32.251 mg/g when pH was 13 in LiOH solution and the time of adsorption equilibrium was 30 h.After being reused 8 times，the adsorption amount maintained at 18 mg/g or more and the lithium adsorption amount in Tibet Longmucuo brine reached 11.273 mg/g. The adsorption process was found to fit pseudo-second-order kinetic equation，so the adsorption process was determined to be chemical adsorption and the kinetics controlled step of adsorbent with Li+ was determined to be particle diffusion control （PDC）.

Key words: ion sieve, lithium ion, adsorption, spinel-type