Effects of NO3-, F-, SO4(super 2-), and CO3(super 2-) on Pb2+ immmobilization by hydroxyapatite

Hydroxyapatite (HA) is an effective cation exchanger, with proven ability to attenuate levels of Pb2+ in contaminated soil material. However, HA is also noted for its isomorphous substitution of Cl and F ions for OH ions in apatite. The effects of NO3, F, SO4 and CO3 ions on Pb2+ immobilization on HA was investigated. The results showed that high levels of these interfering anions did not affect the ability of HA to effectively immobilize Pb2+, indicating that HA can be used to reduce pollution levels of lead-contaminated materials.