2 mg of lanthanum(III) and 2 mL of 5% solutions of 8-hydroxyquinoline
were added to 100 mL of a solution containing 2 lg of
Cd 10 lg of Pb and Ni, and 20 lg of Cu and Zn. The pH value of
the obtained solution was adjusted to 8 using the tetra borate buffer.
Then, the solution was heated in a water bath for 20 min in the
temperature of 50 C. After the formation of the precipitate, the
solution was centrifuged at 3500 rpm for 10 min. The supernatant
was removed. Precipitate was digested in 5 mL of 2 mol L1 solution
of hydrochloric acid. The analytes in the final solution were
determined by ICP-OES and FAAS.