Facile assembly of hollow polydopamine capsules onto macroporous poly(glycidyl methacrylate) foams for simultaneous removal of λ-cyhalothrin and copper ions

Bio-adhesive immobilization of hollow polydopamine capsules (HPDA) onto macroporous poly(glycidyl methacrylate) foams (MPGMA) was implemented via the layer-by-layer assembly in the presence of dopamine “glue”, and then as-prepared HPDA-MPGMA with dual binding sites were employed as adsorbents for simultaneous removal of λ-cyhalothrin (LC) and copper ions Cu(II). The results of characterization showed that HPDA-MPGMA had stable and porous architecture, and the surface morphology and microstructure of HPDA-MPGMA can be finely tuned by adjusting the assembly cycles. In single adsorption, kinetics experiment demonstrated that binding step was fast and that it could be well described by the pseudo-second order-equation where the equilibrium time were 180   min for LC and 60   min for Cu(II). Additionally, the maximum adsorption capacity at 298   K calculated from Langmuir adsorption isotherm were 47.40   mg   g −1 and 12.09   mg   g −1 for LC and Cu(II), respectively. Furthermore, binary adsorption suggested that the enhanced adsorption capacity of LC was 51.59   mg   g −1 and 54.77   mg   g −1 in the presence of 10   mg   L −1 and 30   mg   L −1 Cu(II) at 298   K, respectively, and the same promotion in adsorption ability of Cu(II) was observed when the concentration of coexistent LC ranged from 3.0   mg   L −1 to 5.0   mg   L −1 , indicating the partial complexation of Cu(II) and LC by means of the coexistence at low concentration could slightly improve the simultaneous adsorption.