Phase Transformation of Fayalite from Copper Slag During Oxidation Roasting
Abstract
1. Introduction
2. Experimental
2.1. Raw Material
2.2. Procedures
2.3. Analyses
3. Results and Discussion
3.1. Thermal Analysis of Fayalite
3.2. Phase Transformation of Fayalite
3.3. Magnetic Transformation of Roasted Products
3.4. Microstructure Analysis of Roasted Products
3.5. Discussion of the Phase Transformation of Fayalite
4. Conclusions
- (1)
- During oxidation roasting, fayalite from copper slag first decomposes into amorphous magnetite and silica, then the former is oxidized into hematite while the latter converts into cristobalite solid solution as the temperature increases.
- (2)
- Elevated roasting temperature promotes the decomposition of fayalite into iron oxide and silica. Meanwhile, the iron oxide can migrate to the particle surface. The thickness of the iron oxide layer reaches about 5.0 μm in the roasted product obtained at 1100 °C.
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
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Temperature (°C) | Fe2SiO4 Content (%) | Fe3O4 Content (%) | Fe2O3 Content (%) |
---|---|---|---|
300 | 82.93 | 17.07 | / |
400 | 64.11 | 35.89 | / |
500 | 59.93 | 40.07 | / |
600 | 20.96 | 47.26 | 31.78 |
700 | 15.92 | 50.79 | 33.29 |
800 | / | 35.90 | 64.10 |
900 | / | 32.67 | 67.33 |
1000 | / | 26.24 | 73.76 |
1100 | / | 19.21 | 80.79 |
Position | Mass Fraction (%) | ||||
---|---|---|---|---|---|
O | Fe | Si | Zn | Al | |
A | 31.67 | 50.61 | 14.99 | 2.73 | / |
B | 36.96 | 45.37 | 14.47 | 2.59 | 0.61 |
C | 30.79 | 51.86 | 14.75 | 2.6 | / |
D | 30.96 | 50.39 | 15.2 | 3.54 | / |
E | 39.2 | 46.55 | 12.15 | 2.11 | / |
F | 34.6 | 48.19 | 17.21 | / | / |
G | 29.93 | 52.79 | 15.04 | 2.24 | / |
H | 34.12 | 53.51 | 7.45 | 3.81 | / |
I | 37.53 | 42.91 | 17.24 | 2.32 | / |
J | 29.54 | 68.64 | 1.83 | / | / |
K | 37.68 | 41.08 | 18.3 | 3.21 | / |
L | 30.83 | 69.17 | / | / | / |
M | 37.31 | 40.07 | 17.34 | 3.77 | / |
N | 29.56 | 66.73 | 3.71 | / | / |
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Zhang, X.; Zhao, Y.; Zhou, H.; Wang, X.; Gao, Z.; Wang, H. Phase Transformation of Fayalite from Copper Slag During Oxidation Roasting. Processes 2025, 13, 3317. https://doi.org/10.3390/pr13103317
Zhang X, Zhao Y, Zhou H, Wang X, Gao Z, Wang H. Phase Transformation of Fayalite from Copper Slag During Oxidation Roasting. Processes. 2025; 13(10):3317. https://doi.org/10.3390/pr13103317
Chicago/Turabian StyleZhang, Xiaoxue, Yuqi Zhao, Huili Zhou, Xiangyu Wang, Zhonglin Gao, and Hongyang Wang. 2025. "Phase Transformation of Fayalite from Copper Slag During Oxidation Roasting" Processes 13, no. 10: 3317. https://doi.org/10.3390/pr13103317
APA StyleZhang, X., Zhao, Y., Zhou, H., Wang, X., Gao, Z., & Wang, H. (2025). Phase Transformation of Fayalite from Copper Slag During Oxidation Roasting. Processes, 13(10), 3317. https://doi.org/10.3390/pr13103317