Polyamidoamine Dendronized Hollow Fiber Membranes in the Recovery of Heavy Metal Ions

Polyamidoamine (PAMAM) dendronized hollow fiber membranes (HFMs) were synthesized and used in the recovery of heavy metal ions. The dendronized HFMs showed strong binding ability with Cu(2+), Pb(2+), and Cd(2+) ions. Generation 3 (G3) PAMAM dendronized HFM (G3-HFM) retained 72% of its Cu(2+) binding capacity after five cycles of use and recovery. Interestingly, Cu2(OH)3Cl, Pb3(CO3)2(OH)2, and CdCO3 crystals were grown on G3-HFM surface when G3-HFMs were immersed in CuCl2, Pb(NO3)2, and CdCl2 solutions, respectively, while no crystal was observed with nonmodified HFMs. The results provide new insights into the applications of membrane-supported dendrimers in the recovery of heavy metal ions.