ARTICLE
Low-temperature sintering of low-grade magnesite for magnesium phosphate cement clinker: hydration mechanism and performance regulation
To enable efficient utilization of low-grade magnesite and reduce the production cost of magnesium phosphate cement (MPC), this study developed a low-temperature sintering process (1100–1250°C) to prepare MPC clinker from a Mg(OH)2–Al2O3–CaCO3 ternary system. Based on phase diagram analysis, the raw material proportions were optimized, yielding an optimal molar composition of 58.3:14.6:27.1. Using X-ray diffraction (XRD), isothermal calorimetry, Vicat setting time measurement, and compressive strength testing, the phase evolution, hydration heat, setting behavior, and mechanical properties were investigated. After sintering at 1200°C, the resulting clinker was used to prepare MPC paste, which achieved a compressive strength of 16.3 MPa after 1 day and an initial setting time of 17.15 min. Analysis of the hydration mechanism reveals that Al2O3 retards the hydration process by forming MgAl2O4, whereas CaO enhances early strength through the formation of calcium phosphate hydrates. Compared with conventional high-temperature processes (1500–1800°C), this method reduces energy consumption by over 30%, offering a sustainable pathway for the high-value utilization of low-grade magnesite.
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Cite This Article
APA Style
Deng, Y., Feng, X. (2026). Low-temperature sintering of low-grade magnesite for magnesium phosphate cement clinker: hydration mechanism and performance regulation. ZKG International, 79(6), 79–107. https://doi.org/10.32604/zkg.2026.084786
Vancouver Style
Deng Y, Feng X. Low-temperature sintering of low-grade magnesite for magnesium phosphate cement clinker: hydration mechanism and performance regulation. ZKG Int.. 2026;79(6):79–107. https://doi.org/10.32604/zkg.2026.084786
IEEE Style
Y. Deng and X. Feng, “Low-temperature sintering of low-grade magnesite for magnesium phosphate cement clinker: hydration mechanism and performance regulation,” ZKG Int., vol. 79, no. 6, pp. 79–107, 2026. https://doi.org/10.32604/zkg.2026.084786
