THE ENHANCED REDUCTION OF BROMATE BY HIGHLY REACTIVE AND DISPERSIVE GREEN NANO-ZEROVALENT IRON (G-NZVI) SYNTHESIZED WITH ONION PEEL EXTRACT†

Abstract

In this study, novel green nano-zerovalent iron (G-NZVI) is synthesized for the first time using onion peel extract for the prevention of rapid surface oxidation and the enhancement of particle dispersibility with a high reductive capacity. The results from various surface analyses revealed that the spherical shape of G-NZVI was fully covered by the onion peel extract composed of polyphenolic compounds with C[double bond, length as m-dash]C–C[double bond, length as m-dash]C unsaturated carbon, C[double bond, length as m-dash]C, C–O, and O–H bonds, resulting in high mobility during column chromatography. Furthermore, the obtained G-NZVI showed the complete removal of 50 mg L−1 of bromate (BrO3−) in 2 min under both aerobic (k = 4.42 min−1) and anaerobic conditions (k = 4.50 min−1), showing that G-NZVI had outstanding oxidation resistance compared to that of bare NZVI. ...