Simultaneous adsorption of lead and aniline onto magnetically recoverable carbon: optimization, modeling and mechanism

BACKGROUND: A magnetic Fe3O4/powder activated carbon (Fe3O4/PAC) composite was fabricated as a hybrid adsorbent for the simultaneous removal of Pb(II) and aniline (An) from synthetic wastewater. SEM, EDX, VSM, BET, TEM and XRD analyses were employed for composite characterization. Adsorption experiments in a batch mode were conducted through evaluation of the factors affecting the adsorption process (i.e. pH, contact time, different adsorbent and adsorbate concentrations, and temperature). RESULTS: The adsorption of both contaminants followed pseudo-second-order kinetics. According to the Langmuir isotherm the maximum Pb(II) and An sorption capacities at pH 6.0 were found to be 94.3 and 206.6 mg g(-1), respectively. A comparative study on the performance of the adsorption process in both single and simultaneous systems revealed that the presence of Pb(II) and An together had synergistic effects on the adsorption efficiency. Moreover, the adsorbent performance in the presence of the two pollutants compared with each of them alone was not diminished. CONCLUSION: Fe3O4/PAC shows simple and easy regeneration and good potential reusability, and its adsorption efficiency was preserved effectively even after four successive cycles of use. Fe3O4/PAC could be considered an excellent conducting material for the treatment of metal ions and organic pollutants. (C) 2016 Society of Chemical Industry