Application of Stabilized Nano Zero Valent Iron Particles for Immobilization of Available Cd2+, Cu2+, Ni2+, and Pb2+ Ions in Soil

The present manuscript studies the effectiveness of commercial nano zero valent iron (nZVI) particles in decreasing the availability of Cd, Cu, Ni, and Pb in spiked soil samples and to remove the same heavy metals from aqueous solutions. The difference of nZVI efficiency between single and multi-metal contamination was evaluated. The application of nZVI in water samples showed higher effectiveness in the cases of single metal contamination. The effectiveness of single- and multi-metal (mixtures of Cu, Ni, Pb and Cd, Cu, Ni, Pb) immobilization in soil using different doses (0%, 0.85%, 1.7%, 2.55%, and 5.1%) of nZVI was determined. Immobilization efficiency was assessed using the leaching procedure and depended on a particular metal and the dose of nZVI. In all cases, it was determined that an increasing amount of nZVI resulted in decrease in the leaching of analysed metals. In cases, where higher nZVI doses were used, higher immobilization efficiency was observed for heavy metals in multi-metal contamination. The application of nZVI significantly reduced leaching of all heavy metals and this strategy can be successfully used for heavy metals stabilization in soils. Article HighlightsThe highest removal efficiencies from aqueous solutions were for Cu2+ and Pb2+.The percentages of metal immobilized were higher in multi-metal polluted soils.Using nZVI the exchangeable fraction of heavy metals can be significantly reduced.