Application of greenly synthesised zero-valent iron nanoparticles for iron removal from aqueous system

Abstract

Abstract The green synthesis of nanoparticles, an eco-friendly and easy method, is of great interest due to versatile applications of nanomaterials in multiple fields, especially in water/wastewater treatment. The green synthesis of nano iron particles using Amaranthus dubius leaves extracts using liquid phase reduction was investigated and employed for iron remediation from aqueous system. The synthesized nanoparticles size, surface area, morphology, functional groups, composition, and point of zero charge were investigated. Results showed that A. dubius extract mediated nanoparticles were 1-3 nm spherical particles with aggregations and possessed surface area of 12.76 m2g−1. FTIR exposed the presence of C-O, –NH or –OH stretching and bending vibrations of –CH bonds found in various groups. The effects of different process parameters like pH, contact time, adsorbent dosage and influent iron concentration on iron removal capacity of greenly synthesised zero-valent iron nanoparticle (GnZVI), were examined. GnZVI achieved 47.6% iron removal from a solution having 0.5ppm influent iron at optimised conditions of pH 10 and dose 5gL−1 after 3 h treatment. The removal efficiency was found to decreases with increase in influent iron concentration and reached 31.8% removal for 10 mgL−1 influent iron concentrations. The study revealed the feasibility of utilizing GnZVI for achieving desirable limit of iron for potable purposes from water with lower concentration of iron.