1-(2-pyridylazo)-2-naphthol (PAN) as extractant in solid-liquid extraction of some trivalent rare earth elements

Abstract In the present paper, solid-liquid extraction behaviour of RE(III) (RE  La, Ce, Pr, Nd, Sm, Gd, Dy and Yb) by the use of 1-(2-pyridylazo)-2-naphthol (PAN, HL) as an extractant in paraffin (m.p. 48 ∼ 50°) has been investigated at 80 ± 0.07°. The effect of equilibrium time, pH of aqueous phase, concentration of extractant in paraffin and solid diluent as well as buffer solution used on the extraction efficiency of RE(III) have been discussed. The extraction reacton is RE 3+ + 2HL (o) + Cl − ⇌ REL 2 Cl (o) + 2H +