Studies on preparation of the novel crosslinked chitosan resin and adsorption of benzoic acid

With chitosan as the raw material, a novel resin was prepared through inverse suspension crosslinking by formaldehyde and epichlorohydrin. The structure of the resin was characterized by Fourier transform IR and Scanning Electron Micrograph. The adsorption isotherms of benzoic acid from water onto the novel resin were determined at different temperatures, and the thermodynamic parameters in adsorption process were calculated. The experimental results were fitted with Freundlich equations well. The thermodynamics of the systems was related closely to the adsorption mechanisms. When the concentration of benzoic acid was relatively low, the adsorption was an exothermal process with the system entropy decreasing, and the decrease of temperature did benefit the process. When the concentration of benzoic acid was relatively high, the adsorption was an endothermal process with the system entropy increasing, and the increase of temperature did benefit the process.