Polydopamine-functionalized graphene oxide compounded with polyvinyl alcohol/chitosan hydrogels on the recyclable adsorption of cu(II), Pb(II) and cd(II) from aqueous solution

Polydopamine-Functionalized graphene oxide (PDA-GO) was used to form Polyvinyl Alcohol/Chitosan/PDA-GO (PVA/CS/PDA-GO) hydrogels. FTIR, TGA and SEM investigation showed that PDA had been successfully loaded on graphene oxide nanosheets. Adsorption of metal ions onto the novel PVA/CS/PDA-GO hydrogel beads with variations in pH, contact time, initial metal concentration and temperature had been investigated. Adsorption data were well accurately described by Langmuir isotherm and pseudo-second-order kinetic model at the optimum pH 5.5. The maximum adsorption capacities of the PVA/CS/PDA-GO were 210.94 mg·g −1 , 236.20 mg·g −1 and 214.98 mg·g −1 for Cu(II), Pb(II) and Cd(II) ions with 40 C, respectively. Meanwhile, desorption efficiency and reusability of the adsorbents were assessed on basis of six consecutive adsorption-desorption cycles. This work provides a simple and environmentally friendly method to obtain the PVA/CS/PDA-GO hydrogel beads, which really would be a potential recyclable adsorbent for removal of hazardous metal ions in waste water.