Synthesis and surface protection of nano zerovalent iron (NZVI) with 3-aminopropyltrimethoxysilane for water remediation of cobalt and zinc and their radioactive isotopes

Abstract

A method is described to synthesize a novel magnetic nano-sorbent via surface modification and protection of nano-zerovalent iron (NZVI) with 3-aminopropyl trimethoxysilane for the formation of NZVI-NH₂. The produced magnetic nanomaterial was characterized by FT-IR, SEM, TEM, TGA, surface area analysis (BET) and zeta potential. Based on the TEM analysis, the particle size of the NZVI-NH₂ sorbent was identified in the range 45–46 nm. The NZVI-NH₂ sorbent was examined to evaluate its adsorption characteristics towards cobalt(II), zinc(II) and their radioactive isotopes in aqueous solutions and water samples using the batch equilibrium and microcolumn techniques. The metal capacity values of Co(II) and Zn(II) were optimized in the presence of different physico-chemical parameters such as pH, contact time, sorbent dose, metal ion concentration and interfering ions on the adsorption process. We also aimed to explore, investigate and evaluate using the microcolumn technique the potential applications of the NZVI-NH₂ adsorbent for remediation of cobalt(II), zinc(II) and their radioactive isotopes from radioactive wastewater samples.