The cross‐linked hyperbranched polyamide‐amines: The preparation and its adsorption for Pb(II)

Abstract In order to prepare a new adsorbent material for the treatment of waste water containing Pb(II), hyperbranched polyamide‐amines (H‐PAMAMs) were prepared via one‐pot method, then the H‐PAMAMs were crosslinked by epichlorohydrin. The crosslinked hyperbranched polyamide‐amines (C‐H‐PAMAMs) were prepared and characterized. The selective adsorption of coexisting ions shows that the C‐H‐PAMAMs have high adsorption capacity and selectivity for Pb(II). The adsorption characteristics and mechanism of the C‐H‐PAMAMs for Pb(II) were systematically investigated. The results of batch adsorption experiments showed that the maximum Pb(II) adsorption capacity was 180.83 mg/g at pH 4.0 and 318 K. The adsorption process on the C‐H‐PAMAMs was well described by the Langmuir model, which indicated the adsorption process was spontaneous and endothermic. The X‐ray photoelectron spectroscopy analysis showed that the adsorption mechanism of the C‐H‐PAMAMs for Pb(II) was the synergistic chelation of COO and CONH. Four adsorption/desorption recycling tests showed that the the C‐H‐PAMAMs still had a high adsorption capacity for Pb(II).