Preparation and characterization of porous chitosan tripolyphosphate gel bead

In this study, Chitosan TPP beads and Chitosan TPP beads in the presence of PEG was prepared. PEG was added to achieve porosity after the removal of the polymer. The samples were characterized by FTIR and SEM analysis. The swelling behaviour was followed in pH 1.2, 7, and 11 and their Fe3+ ion adsorption rate from aqueous solution was determined at pH 1.2. Beads prepared both in the presence and absence of PEG contained porosity. Chi-TPP porous beads prepared by PEG leaching method swelled more in aqueous media having a swelling ratio of about 3500% in acidic media, 350% in neutral media and 400% in basic media as compared with Chi-TPP beads with swelling ratio of 2000% in acidic media, 150% in neutral media and 200% in basic media. The beads served as effective adsorbents for Fe3+. The Chi-TPP PEG beads showed a better adsorption capacity for Fe3+ and better swelling behavior as a result of increased hydrophilicity due to PEG treatment. The adsorption behavior obeyed Langmuir model and the kinetics followed pseudo second order. Keywords: Chitosan, Polyethyleneglycol, Fe3+ adsorption.