83 / 2016-06-13 10:43:46

REMEDIATION OF CR(VI), CU(II) AND PB(II) AQUEOUS SOLUTIONS USING FUNCTIONALISED ZERO-VALENT IRON NANOPARTICLE

Introduction – The population increase as urban and industrial activities have to led to elevated concentrations of a wide range of contaminants in wastewater and groundwater, within which highlights the presence of Cr (VI), Cu(II) and Pb(II) due to its high toxicity, which affected the health of millions of people worldwide.
zero-valent iron nanoparticle (nZVI) has proved an effective tool for the treatment of wastewater because of its large surface area and specific affinity for toxic contaminants in aqueous systems.

Experimental - nZVI nanoparticles were synthesized by the aqueous chemical reduction method of ferric salts at room temperature in absence of inert conditions. The obtained nanoparticles were characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD). It was also evaluated the effectiveness of nZVI nanoparticles as a cost-effective solution in the removal of Cr (VI), Cu(II) and Pb(II) in aqueous medium, evaluating amount of nZVI, and the contacting time with Cr (VI), Cu(II) and Pb(II), looking to optimize the operation condition for the use of nZVI.
Results and Discussion - The X-ray diffraction pattern for shows a peak at 44 °, demonstrating the presence of nZVI. Average size of zero-valent iron nanoparticles was found around 4.5 nm (Image 1). The speficic surface area was mesearument in 170,000 m2/Kg. The reduction potential of nZVI nanoparticles at a concentration of 0.4 g L-1, 0.4 g L-1 and 0. 2 gL-1 for Cr(VI), Cu(II) and Pb(II) correspondingly was found to be >95% in 1 h.

Conclusions – nZVI it has proven to be an efficient tool in Cr(VI), Cu(II) and Pb(II) removal through reduction/immobilization and also in reducing the toxicity due to heavy metal ions with high concentrations. stirring in all cases more than 90% of contaminant in wáter in short periods of time.