Removal and regeneration of aqueous divalent cations by boehmite

Boehmite (Al(OH)O) was employed for the removal of aqueous Mg2+, Cu2+, Cd2+, Pb2+, and Co2+ at 298 K. Although boehmite was able to remove these divalent cations, the greater removal rate with boehmite of Pb2+ (28.7%) than with Mg-2+, Cu2+, Cd2+, and Co2+ (5.6, 25.3, 10.9, and 13.3%, respectively) was observed under acidic conditions. Under stronger alkaline conditions, in which the lead species was completely dissolved, a greater removal rate of Pb2+ (more than 80%) was observed under the corresponding conditions employed for the acidic conditions. The removed lead species could not be dissolved from boehmite in an acidic solution while an evident dissolution of lead species was detected using an aqueous NaOH Solution. The results shown in the present study reveal that boehmite can be employed as a reagent for the removal and regeneration of aqueous metal cations. (C) 2008 Elsevier Inc. All rights reserved.