Enhanced Nitrate Reduction by Polyvinylpyrrolidone Stabilized Nano-scale Zero-valent Iron
The aim of this work was to investigate the effect of Polyvinylpyrrolidone (PVP) on the proprieties and reactivity of nZVIs. The nZVI has been considered as an efficient material for removing the undesired contaminants from water. However, the drawbacks of nZVI such as oxidation and aggregation phenomena largely limit its reactivity. Therefore, PVP was integrated into nZVI to overcome the oxidation and aggregation problems of the particles. Transmission electron microscopy (TEM), X-ray diffraction (XRD) analyses and energy dispersive X-ray spectroscopy (EDS) techniques were performed. Different PVP loads ranged between 0.2 to 2 (g/L) were undertaken, a load of 0.6 (g/L) was the optimum ratio to show the nZVI with good properties without forming aggregates. Comparing with bare-nZVI, the PVP stabilized nZVI showed an excellent performance for nitrate removal. The environmental factors effect such as pH and initial nitrate concentration were investigated. The experimental data and reactions kinetics were explained by investigating four different models. The current work suggests that the PVP strongly proposed as an effective polymer for enhancing the properties and reactivity of nZVI for the practical application. Keywords - Nanoscalezerovalent iron, Polyvinylpyrrolidone, Nitrate removal, Characterization, pH effect, Kinetic rate.