Abstract
Manganese oxide adsorbents containing pentavalent metal (V, Nb, Sb, or Bi) were prepared by acid treatment of pentavalent metal-doped lithium manganese oxide with spinel structure. Their lithium adsorptive properties in sea water were studied batchwise. The addition of Nb, V, or Bi caused an increase in the lithium adsorptive capacity by 25-30%. The Nb-containing adsorbent seems to be the most promising adsorbent among the pentavalent metal-doped manganese oxides due to its high chemical stability and large adsorptive capacity for lithium in sea water. The increases in the lithium uptake by doping Nb could be explained by the increase in the number and the acidity of adsorption sites selective to lithium ions.
