Synthesis and characterization of a novel fish scale-immobilized chitosan adsorbent--preliminary features of dichlorophenol sorption by solution calorimetry

Abstract

Brazilian Corvina fish scales were cross linked with polyglutaraldehyde and chemically modified with chitosan gel. Characterization has pointed that chitosan has good and stable adhesion on the fish scales. The sorption of dichlorophenol-2,6-indophenol (DPI) on the novel material was studied by isothermal solution calorimetry. The non-symmetric shapes of the calorimetric plots indicate that the DPI sorption sites of the adsorbent are not energetically uniform. The enthalpies of the DPI sorption processes were highly exothermic (from -536.7 to -50.9 kJ mol(-1)). The analysis of both the characterization of the materials and the calorimetric results has suggested that the interactions at the fish scales/DPI interface are due to surface reactions. The present work underlines the excellent features of the new fish scale-based adsorbent for use in phenol sorption applications at solid/solution interfaces.