TY  - JOUR
AU  - YANG, Qingchun
AU  - WU, Jiaming
AU  - HU, Changqing
AU  - NIU, Teng
AU  - HAN, Xiangyu
AU  - FENG, Xueyan
AU  - YE, Zhengmao
PY  - 2022
TI  - Evolution and Formation Kinetics of Gehlenite Phase in Ordinary Sulfoaluminate Cement Clinker with Low Al2O3/SiO2 Ratio
JO  - Journal of the Chinese Ceramic Society
SN  - 0454-5648
SP  - 1972
EP  - 1977
VL  - 50
IS  - 7
AB  - To reveal the mechanism of the inert gehlenite (C2AS) phase in sulfoaluminate cement clinker at a low Al2O3/SiO2 ratio, a series of clinkers were prepared at different calcination temperatures and holding time as well as a fixed Al2O3/SiO2 ratio of 2. The evolution of C2AS was investigated by X-ray diffraction combined with the Rietveld method and thermogravimetry-differential scanning calorimetry. The results show that C2AS is produced by the reaction of CaO, SiO2 and Al2O3 at 950-1200 ℃ . C2AS is mainly produced by the reaction of CA and CaO decomposed from C4A3＄ with the residual SiO2 when the temperature exceeds 1200 ℃ . It is indicated that the kinetics of the C2AS formation above 1200 ℃ is mainly controlled by the diffusion of Ca2+, and the activation energy of the reaction is (305±20) kJ/mol. This study provides a a guidance for the use of low-grade bauxite in the calcination of sulfoaluminate cement clinker.
UR  - https://doi.org/10.14062/j.issn.0454-5648.20211015
DO  - 10.14062/j.issn.0454-5648.20211015