Magnetite nanoparticles coated with methoxy polyethylene glycol as an efficient adsorbent of diazinon pesticide from water

Abstract

Methoxy polyethylene glycol modified magnetite nanoparticles (PEGMNs) were synthesized and characterized by scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), and X-ray diffraction (XRD). The adsorption of diazinon onto PEGMNs was investigated by UV-Vis spectrophotometry at 236 nm, through batch experiments. The effects of adsorbent dosage, solution pH, contact time, solution temperature and water impurities on the adsorption of diazinon onto PEGMNs were investigated. The process of adsorption was increased rapidly in the first contact period of 10 min. The adsorption at equilibrium (qe) was found to increase with increasing pH. The results of diazinon removal at various PEGMNs dosages demonstrated that the optimum dose of PEGMNs was 1mg. The amount of adsorption of diazinon at equilibrium increased with an increasing temperature from 15°C to 45°C that indicateds an endothermic process. Therefore, PEGMNs were used as an efficient absorbent for the removal of diazinon.