Preparation and Application of a Magnetic Graphene-Based Nanocomposite for Pesticides Removal

Pollution of water by pesticides and industrial wastes has been recognized as a primary health hazard for human and animals. The effective removal of the toxic pollutants with the economic and environmental advantages is necessary. The toxic pollutants removal by adsorption on metal oxides has shown enormous potential. The nanoscale metal oxides with large surface area, porous structures, large number of active sites, easy recovery, and low toxicity have excellent performance for the adsorption and remediation of contaminants. This work reports the preparation of a magnetic graphene-based nanocomposite containing oxide nanoparticles of molybdenum disulfide and cerium oxide (GO-Fe3O4/MoS2/CeO2). The synthesized nanostructure was characterized by XRD and FESEM-EDX. This nanostructure was investigated as an adsorbent in a magnetic solid phase extraction (MSPE) process for the removal of organophosphorus pesticide (OPPs) of fenitrothion from aqueous media. Batch mode adsorption studies were performed to evaluate the adsorption kinetics and adsorption isotherms. The proposed adsorbent combines the advantages of superior adsorption capability and magnetic separability to easy isolation from sample solutions. The effective experimental parameters on the extraction recovery of fenitrothion including extraction time, pH, adsorbent amount, pesticides concentration, and desorption conditions were investigated and optimized. Under the optimal conditions, Fast magnetic separation of nanoparticles from sample solution (< 1min), optimized pH (at neutral pH) and low extraction time (about 5 min) are the merits of the prepared adsorbent. These results indicated that the proposed nanostructures had the great adsorptive ability and can be applied in a fast, simple and efficient MSPE technique for OPPs extraction in different matrices.