Preparation of the Iron Oxide Red from the Converter Dust by the Magnetic Separation and Roasting Process

Abstract

Preparation of iron oxide red (α-Fe2O3) from the converter dust by the superconductivity high gradient magnetic separation (S-HGMS) and roasting process was investigated in the paper. The basic properties of the dust were studied by the X Ray Fluorescence, the chemical analysis and the X Ray Diffraction methods. The results showed that the raw dust mainly contained elements of Fe‵O‵Si‵Ca, the iron content of the raw dust was 61.80%, and there were ferrous phases of Fe3O4, α-Fe2O3, Fe2(SiO4) and CaFe(Si2O6) in the raw dust. Under the optimum conditions of magnetic field intensity of 1.8T, the dispersion agent of 30mg/L and velocity of 500mL/min, the powders absorbed by the magnetic medium mainly contained Fe3O4 and α-Fe2O3, and the iron content of powders absorbed was up to 65.90%. The Fe2+ content of the powders absorbed under the optimum magnetic conditions dropped to 0.25% from 19.10% after roasting of fifty minutes, and the iron content of powders absorbed under the optimum magnetic conditions fell to 64% due to oxidation, and the Fe3O4 was removed. Finally the α-Fe2O3 content was up to 91.07% in the iron oxide red.