Plackett–Burman experimental design for the removal of diazinon pesticide from aqueous system by magnetic bentonite nanocomposites

The present study demonstrates the effective removal of diazinon pesticide from aqueous solutions by means of magnetic bentonite nanocomposite. The product was characterized by advanced techniques like scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX) and infrared spectroscopy (IR). Operational parameters affecting the removal efficiency, including the pH level, contact time, agitation speed and adsorbent dose, were screened through Plackett-Burmann design to determine the significant factors. Then, significant parameters, including the pH level and adsorbent dose, were further optimized using Central Composite design to predict optimum removal conditions. Under the optimal conditions, the maximum adsorption capacity of the nanocomposite for diazinon was found to be 92.50 %. The kinetic of pesticide sorption and equilibrium studies were performed. The experimental data could be well fitted to the Freundlich model. The magnetic bentonite nanocomposite was successfully applied for the uptake of diazinon from industrial wastewater and groundwater samples and separated easily by means of magnetic separation.

Keywords:

Magnetic bentonite nanocomposites , Diazinon removal , Aqueous system , Plackett–Burman design