Preparation of microsized hematite powder from ferrous sulfate via microwave calcination

• Published in: Journal of Central South University 2017-08, Vol.24 (8), p.1720-1726
• Main Authors: Liu, Bing-guo, Yu, Yan-tao, Peng, Jin-hui, Srinivasakannan, C., Zhang, Li-bo, Guo, Sheng-hui
• Format: Article
• Language: English
• Subjects: Engineering; Hematite; Iron sulfates; Metallic Materials; Particle physics; Particle size distribution; Quality; Roasting; Scanning electron microscopy; Sulfur
• ISSN: 2095-2899; 2227-5223
• DOI: 10.1007/s11771-017-3579-5

The preparation of microsized hematite powder from ferrous sulfate using microwave calcination was investigated based on the TG/DTG curves. The decomposition of industrial ferrous sulfate under air atmosphere was divided into three stages, and a ferrous sulfate sample added with 15% Fe 2 O 3 could strongly absorb microwave energy. Therefore, preparing hematite powder from ferrous sulfate using microwave calcination was feasible. Hematite was obtained under the following optimized conditions: calcination temperature, 850 °C; microwave power, 650 W; and sample amount, 40 g. The obtained hematite satisfied the first-grade quality requirements. The total ferrum value was more than 58%, and the total sulfur and phosphorus contents were less than 0.5% and 0.2%, respectively. X-ray powder diffraction and scanning electron microscopy were used to characterize the structure and morphology of microsized hematite powder. The particles were non-spherical in shape, and the average particle size distribution was 10.45 μm. This work provides new potential applications for waste ferrous sulfate.