Removal of copper(II) from aqueous solutions by flotation using limestone fines as the sorbent and oleic acid as the surfactant

The removal of toxic copper(II) from aqueous solutions was investigated usi ng limestone fines (LS), which are inexpensive and widespread over the glob e, as the effective inorganic sorbent with oleic acid (HOL) as the surfacta nt. The main parameters (i.e. initial solution pH, sorbent, surfactant and copper concentrations, stirring times, temperature and presence of foreign ions) influencing the sorption and flotation processes were examined. The r esults obtained showed the removal of more than 98% Cu-II at pH 7. It was a lso found that the addition of sodium and magnesium ions as activators enha nced the efficiency of copper separation. The procedure was successfully ap plied to recover copper spiked to some natural water samples. A mechanism f or sorption and flotation is suggested.