Removal of heavy metal ions from aqueous solutions by synthetic apatites using the column ion-exchange method

Abstract

The removal of ions such as Al3+, Mn2+, Cu2+, Zn2+, Cd2+ and Pb2 + in aqueous solutions by synthetic apatites has been investigated using the column method. Under the same conditions, hydroyapatites were more selectives that carbonate apatites for cations remotion. Using hydroyapatites, the ranking of ions according to amount exchanged was as follows: Mn2+ < Zn2+ < Cu2+ < Cd2+ < Al3+ < Pb2+. The order of the ions was similar to that observed in previous works using the batch method. XRD and IR analysis indicated the formation of a single phase of Pb2+ ion-exchanged.

hydroxyapatites; carbonate apatite; ion exchange; heavy metal