Thermal Decomposition of Siderite Ore in Different Flowing Atmospheres: Phase Transformation and Magnetism

ABSTRACT

Siderite ore (FeCO₃) is an important iron ore resource that is widely distributed around the world. However, it is difficult to process using conventional methods owing to the low iron grade, easy sliming, and high impurity content. Based on the mechanism of thermal decomposition, the combination of metallurgy and processing is a promising method to process siderite ore. In this study, experiments on thermal decomposition were performed using a fluidization reactor in flowing atmospheres of N₂, CO, and CO₂. The phase transformation and magnetism were characterized via X-ray diffraction, Mössbauer spectroscopy, and vibrating sample magnetometry. The results indicated that the thermal decomposition of siderite ore exhibited significant differences in various atmospheres, particularly for the phase transformation and magnetism, which primarily depended on a two-step function: FeCO₃ → FeO + CO₂ → Fe₃O₄ + CO. It has implications for the utilization of siderite ore resources.

KEYWORDS:

• Siderite ore
• thermal decomposition
• phase transformation
• magnetism

Acknowledgments

The authors thank the National Natural Science Foundation of China (Nos. 51734005, 51874071, 52104249) for their financial support. We acknowledge the Center for Advanced Mössbauer Spectroscopy, Mössbauer Effect Data Center, Dalian Institute of Chemical Physics, CAS, for providing the Mössbauer measurement and analysis.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [51734005,51874071,52104249].