Effect of beading parameters on cross-linked chitosan adsorptive properties

Publication date: Available online 3 September 2019Source: Reactive and Functional PolymersAuthor(s): Mohammadtaghi Vakili, Amin Mojiri, Haider M. Zwain, Jing Yuan, Abdulmoseen S. Giwa, Wei Wang, Fatemeh Gholami, Xiaogang Guo, Giovanni Cagnetta, Gang YuAbstractAmong countless applications, chitosan has the potential to be an effective and cheap adsorbent for pollutant removal in (waste) water. In form of beads, it also exhibits good mechanical and fluid dynamic properties that are suitable for utilization in large-scale adsorption processes (e.g. as column packing). The present study investigates the beading process to prepare chitosan and cross-linked chitosan beads by phase inversion method. Beading parameters (i.e. chitosan amount, acid concentration, non-solvent agent concentration, and temperature) are optimized to obtain an appropriate adsorbent structure to uptake large organic molecules (reactive red 2, a dye, is utilized as model pollutant). Chitosan beads present remarkably enhanced adsorption capacity, mainly thanks to increased specific surface area and porosity. The addition of a cross-linker (diepoxyoctane) further improves pollutant removal. The adsorption process is well-fitted by the Freundlich model, suggesting a multilayer adsorption. The kinetic study also substantiates the complexity of the adsorption mechanism on bead surface, which, however, is satisfactorily predicted by a simple fractal kinetic model. Finally, it is proved that chitosan and cross-link...

Source: Reactive and Functional Polymers - September 4, 2019 Category: Chemistry Source Type: research