Magnetic ZnFe 2 O 4 nanotubes (ZFONTs) with numerous pores on their walls were synthesized and characterized. They are shown to be a viable sorbent for dispersive micro-solid phase extraction of the trivalent ions of rare earth elements (REEs), specifically of lanthanum, praseodymium, europium, gadolinium, holmium and ytterbium. The specific surface area of ZFONTs is large (57m 2 ⋅g −1 ) and much bigger than that of ZnFeO 4 nanoparticles (16m 2 ⋅g −1 ). It is shown that REEs are quantitatively retained on ZFONTs in the pH range of 7.0–9.0....
