Application of Monoalkyl Phosphates to Ion Flotation

Abstract

The objective of this investigation was to determine the feasibility of ion flotation for the selective removal of Pb(II) from dilute aqueous solution, using the monoalkyl phosphates(AP). All the experiments were carried out in a cylindrical column, 42 cm in height and 6.5 cm in diameter (Fig.1).
The maximum degree of elimination of metal ion in dilute aqueous solution occurred at high pH(about 8-10), whereas he high degree of selectivity occurred at low pH (near 4) (Fig.6-10). From the acid aqueous solution containing Zn(II), Cd(II), Cu(II), Ca(II) and Pb(II), Pb(II). could be floated by sodium monostearyl phosphate, leaving the other cations in solution (Fig.14, 15). The scum(AP-metal complex) was normally prepared in 1: 1 molar ratio of AP: M, (II)(M: metal) at pH 4, (Fig.11, 12). By treatment with mineral acid, 95% of the AP and Trital ion were recovered from the scum. The order of stability of these AP-metal complexes was as follows: Pb>Zn>Cd>Cu>Ca (Fig.16).