Characterization and application of magnetite Particles, synthesized by reverse coprecipitation method in open air from mill scale

The industrial grade gram scale fine magnetite particles were synthesized from the mill scale. Mill scale, the reactant in this study, has higher ferrous to ferric ratio (similar or equal to 2), in contrary to the standard ratio (0.5) required for the synthesis of spinel crystalline magnetite. A reverse coprecipitation method was developed for direct synthesis of magnetite particles without any arrangement for oxidation or reduction of ferrous or ferric ions present in the reactants. Particles were aged at two different pH levels (8 and 12) after synthesizing at higher pH and their stability and characteristics were compared. XRD confirmed the cubic spinel structure of magnetite. In agreement with XRD and Raman spectroscopy, FTIR identified the Fe-O band in octahedral and tetrahedral sites indicating the formation of cubic crystalline magnetite. The magnetization value was determined 68 emu/g. Spherical structures of magnetite were confirmed by SEM and TEM analysis. Specific surface area of black and brown magnetite was determined 75.7712 and 64.4382 m(2)/g, respectively. Newly synthesized magnetite particles were found very effective for the adsorptive removal of phosphate and arsenic from the contaminated water.