半湿法合成高性能MnO2·0.5H2O离子筛用于锂沉淀母液中选择性提锂研究OA

The spinel precursor Li1.6Mn1.6O4 was synthesized via a solid-state reaction,followed by hydrochloric acid treatment to obtain the lithium-ion sieve MnO2·0.5H2O.Physical characterization revealed that both the polycrystalline precursor Li1.6Mn1.6O4 and the MnO2·0.5H2O ion sieve maintained nearly pure spinel structures,exhibiting high structural stability during the adsorption-desorption process.Calcination at 425℃,with a Li/Mn molar ratio of 1.1,resulted in the lithium-ion sieve MnO2·0.5H2O,prepared by acid washing the precursor with 0.1 mol/L hydrochloric acid,achieving an adsorption capacity of up to 34.617 mg/g,with only a 1.49%manganese leaching loss.Its adsorption behavior conformed to the Langmuir isotherm model and pseudo-second-order kinetics model,indicating that the MnO2·0.5H2O ion sieve possessed uniform adsorption sites during the Li+adsorption process,and that process was characterized as chemical adsorption.In separation experiments using simulated solutions,it was found that the MnO2·0.5H2O ion sieve exhibited a high selective adsorption capacity for Li+in simulated solutions with high concentrations of Na+and K+.Therefore,this adsorbent can be effectively applied for Li+recovery from lithium precipitation mother liquor.