CHAIN-LIKE ZERO-VALENT IRON FOR FAST DEGRADATION OF METHYL ORANGE (MO) IN WASTEWATER

Abstract

Zero-valent iron nanomaterials with a chain-like structure (Fe[Formula: see text]) were prepared by a facile solution reaction at room temperature. Then, the as-prepared Fe[Formula: see text] and micro-sized iron materials ([Formula: see text]) were comparatively applied in removal of methyl orange (MO) in wastewater. Results indicated that the as-synthesized Fe[Formula: see text] exhibited a chain-like structure which was made of many nanospheres with the size of 80[Formula: see text]nm. Most importantly, compared with [Formula: see text], the chain-like Fe[Formula: see text] has higher reactive performances and could quickly and completely decompose MO in water. In comparison, the Fe[Formula: see text] exhibited structurally enhanced performance of degradation of MO. The kinetic model for oxidation of MO in water matches the first-order equation. The reasons can be attributed to a large number of interfaces in the chain-like Fe[Formula: see text] which leads to rapid dissolution rate of Fe[Formula: see text] and subsequently produces lots of hydroxyl radicals ([Formula: see text]OH) in water. The experimental results further confirmed that these kinds of chain-like iron nanomaterials with proper size could be used as new type Fenton-like materials without H2O2 addition to effectively remove dyes. Moreover, Fe[Formula: see text] would be completely transformed into magnetite (Fe3O4) nanomaterials which could also be conveniently separated from wastewater by a magnet.