Adsorptive removal of azide ion from aqueous solutions using modified activated carbon magnetic nanocomposite

In this work, the activated carbon/magnetic Fe3O4 nanocomposite was synthesized and characterized by TEM and XRD measurements. This magnetic nanocomposite was modified with cetylpyridinium chloride (CPC) and thus used as a new adsorbent for removal of azide ion from an aqueous solution. In an aqueous solution of azide ion, the adsorption capacity was evaluated using both the Langmuir and Freundlich adsorption isotherm models. The main factors affecting the removal of azide ion, such as pH of solution, dosage of adsorbent, surfactant amount and contact time have been investigated in order to find the optimum adsorption conditions. The experimental data were analyzed by the Langmuir and Freundlich adsorption models. Equilibrium data fitted very well with the Langmuir model and the maximum predicted adsorption capacities (qmax) was found to be 22.22 mg g −1 . It was shown that the sorbent can remove more than 95% of azide ion within the first 20 min of contact time. The results indicated that the modified magnetic nanocomposite can be successfully employed in removal of azide ion from water samples.