Use of in-situ synthesized magnetic ferrite to remove heavy metals from waters

Abstract

Exposure to low levels of Pb(II) and Cd(II) is a public health concern, particularly in developing countries where regulations are more permissive. The consequences of such exposure are very serious, especially for infants, children and pregnant women. Therefore, it is necessary to investigate rapid, economical and feasible methods for its elimination, being this goal the purpose of this work. A novel procedure for the simultaneous removal of both species in water at different concentrations by in situ formation of magnetic nanoparticles (Fe3O4) is discussed here. Optimization of the experimental conditions led to approximately 100 % removal efficiency in only 5 min. The sorbent material was characterized by scanning electron microscopy and energy dispersive X-ray microanalysis. In addition, the removal process of Pb(II) and Cd(II) was characterized by adsorption Langmuir isotherms. The thermodynamics of the removal of both species, Pb(II) and Cd(II), from water has been studied by fitting the adsorption isotherms and calculating the Gibbs free energy and enthalpy of the process. The results indicate that the adsorption process can be explained as a combination of physical and chemical adsorption. Moreover, the findings of this work show a faster and more economical process than those previously described, which also allows a simultaneous removal of both metals.

Keywords

• Lead
• Cadmium
• Magnetic nanoparticles
• Removal
• Water contamination