Preparation of magnetic nanocomposite based on polyaniline/Fe3O4 towards removal of lead (II) ions from real samples

In the present study, the surface of the magnetic nanoparticles was modified by cetyltrimethylammonium bromide and polyaniline polymer. The modified nanocomposite was examined as a strong absorbent for the removal of lead ions (II) from the industrial effluent samples. In order to characterize the nanocomposite, a transmission electron microscope was used to determine the exact size of the nanoparticles and the BET technique was used to determine the effective absorbent level. Moreover, CHNS and TGA analyses were used, respectively, to confirm the coating of polyaniline polymer on Fe3O4 magnetic nanoparticles and to study the thermal stability of the modified nanocomposite. Atomic absorption spectrophotometer was also used to determine the amount of lead ion in the solution. Characteristics that influence the removal of lead ions, including pH, adsorbent amount and contact time, were optimized at various temperatures. The optimal pH was obtained to be 9.3, the optimal amount of adsorbent was determined as 3 mg and the optimal contact time was obtained to be 60 min. In addition, this study was conducted to investigate the lead ion (II) in true samples with appropriate substrates. The equilibrium data obtained from the lead adsorption on nanocomposite showed better fitting by Langmuir isotherm compared to Freundlich isotherm. Furthermore, the maximum lead (II) adsorption capacity on Polyaniline/Fe3O4 nanocomposite was 111.11 mg/g. Kinetic studies also showed that the adsorption process followed the pseudo second-order kinetics equation.