Application of composite chitosan-based aerogels in Cr(III) adsorption

The adsorption performance of composite chitosan-based aerogels (CSA) on heavy metal Cr(III) was studied. Using chitosan and citric acid as raw materials, the two solutions were crosslinked with glutaraldehyde to modify chitosan. Then, by vacuum freeze-drying, composite chitosan-based aerogel material (CSA) was prepared and characterized. Taking Cr(III) in the tannery wastewater as the adsorption object, the optimal adsorption conditions were explored through adsorption single-factor experiments. Under this condition, the experimentally measured value of the Cr(III) adsorption capacity of CSA was 175.72 mg/g. Isothermal and kinetic models were established, and the experimental data were consistent with the Freundlich isothermal model and the quasi-secondary kinetic model. The experimental data showed that the adsorption process was mainly multi-layer adsorption dominated by chemisorption and ion exchange.