Removal of Congo Red using biopolymeric aerogels

Abstract

Aerogels were obtained by freeze-drying chitosan (Q)-glutaraldehyde (GA) cross-linked hydrogels that were also modified by the addition of microcrystals of cellulose (MCC). These aerogels were characterized by evaluating their density, porosity, swelling degree, and stability in an aqueous medium, properties that were found to be composition-dependent. To assess their behavior as adsorbents, kinetic tests were performed using the anionic dye Congo Red (CR). The experimental data were fitted using the pseudo-second-order (PSO) model in both aerogels (with and without MCC). The modified aerogels exhibited better stability in aqueous medium and higher adsorption capacity under the studied conditions.