Easy, fast, and efficient removal of heavy metals from laboratory and real wastewater using electrocrystalized iron nanostructures

摘要

The effect of electrooxidation of iron on cobalt and cadmium removal was investigated. This study was initially performed on the laboratory samples and then the real wastewater of two rivers in Iran called Karun and Seimareh were studied. The effect of applied voltage (5-25 V), contact time (10 to 60 min), initial concentration of heavy metal (50-500 ppm), pH (1 similar to 13), and also different organic additives to the water sample on removal efficiency of the species were investigated. The water samples before and after treatment and also the sludge samples were characterized. The results showed that experimental parameters are affected on removal performance. Furthermore, the type of organic attached at the particles surface plays an important role on adsorption process. The atomic absorption spectroscopy results showed that the removal percentage of the species under 25 V, reaction time of 60 min, and initial concentration of cobalt 200 ppm at pH = 11 and cadmium 100 ppm at pH = 5 is about 100%. In continuation of this work, electro-crystallized magnetite nanoparticles modified with thiourea and sodium butanoate in the particle size range of similar to 20-95 nm were developed for the adsorption of antimony (Sb) from wastewater. The effects of different functional groups and the mean particle size on removal of antimony were also studied. The ICP-MS results confirmed the surface modification of magnetite particles by amine group provides specific functionalities that can enhance the capacity of iron oxide nanoparticles for Sb uptake in water treatment procedures.