关键词: 铁尾矿, 硫酸焙烧法, α-Fe2O3光催化剂, 降解率

Abstract: Iron tailings are rich in valuable elements such as iron and silicon， which can be used as raw materials to prepare functional materials. The possibility to prepare α-Fe2O3 photocatalyst by iron extracted from iron tailings with sulfuric acid roasting was investigated， and the effects of acid to ore mass ratio， roasting temperature and roasting time on the extraction rate of iron in the roasting process were studied. The suitable roasting conditions were obtained in the condition of the acid to ore mass ratio of 2∶1， the roasting temperature of 280 °C and the roasting time of 2 h， in which the iron extraction rate was up to 89.80%. The iron-containing sulphate solution obtained by water leaching and filtering process with roasting clinker was treated by a neutralization precipitation method to prepare iron-containing precursor， and then calcined at 400 °C for 2 h to obtain α-Fe2O3 with a particle size of 40~50 nm， which performed good dispersibility. When α-Fe2O3 was used as photocatalytic for degradation of methyl orange， the adsorption rate of dark reaction was 56% for 20 min， and the photocatalytic degradation rate was 99% for 120 min， indicating that α-Fe2O3 has good photocatalytic performance. The results realized the comprehensive ultilization of iron from the tailings and promote practice of the photocatalytic.

Key words: Iron tailings, Sulfuric acid roasting method, α-Fe2O3 photocatalysis, Degradation rate