Biopolymer magnetic chitosan–graphene oxide composite for removal and extraction of aromatic amines from aqueous samples

BACKGROUND Magnetic chitosan was crosslinked with graphene oxide and a magnetic chitosan–graphene oxide composite was synthesized and characterized. The composite was used for the removal and extraction of aromatic amines like aniline, N,N‐dimethylaniline and N,N‐diethylaniline. RESULTS Experimental factors affecting the adsorption process such as solution pH, time of contact, amount of adsorbent, initial concentration of analyte and temperature of solution were studied. The maximum adsorption capacity was found to be 7.55 mg g−1 for aniline, 6.96 mg g−1 for N,N‐dimethylaniline and 6.86 mg g−1 for N,N‐diethylaniline using pH 7 at room temperature. Kinetic and adsorption isotherm models were applied to the data which showed the best fit of experimental data to pseudo‐second‐order kinetic model and Langmuir isotherm for all three analytes. CONCLUSIONS The adsorption process was found to be spontaneous and exothermic as revealed by thermodynamic study. The maximum recoveries for aniline, N,N‐dimethylaniline and N,N‐diethylaniline were 98.56%, 97.05% and 95.26%, respectively. Successful application of the adsorbent was found for spiked aqueous samples. © 2022 Society of Chemical Industry (SCI).