A novel green biosorbent from chitosan modified by sodium phytate for copper (II) ion removal

A novel kind of adsorbent bead was prepared from chitosan (CS) by ionic-linked with sodium phytate (SP) and then covalent cross-linked with epichlorohydrin (ECH) by nonsolvent-induced phase separation. The structure of the beads was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The adsorption properties of the beads for Cu(II) ions under different adsorption conditions were investigated. The maximum adsorption capacity of Cu(II) ions was 177.1mgg(-1) at the conditions of pH of 5.2, temperature of 50 degrees C, and initial Cu(II) ion concentration of 728.3mgL(-1). The adsorption isotherm of Cu(II) ions on the CS/SP/ECH beads was well correlated with the Langmuir isotherm model, and the whole adsorption process could be better followed the pseudo-second-order kinetic model. Moreover, the CS/SP/ECH beads still exhibited good adsorption capacity even after the 15th regeneration cycles.