Study on fired temperature and micro-morphology of white alinite cement

A new type of white cement was prepared using limestone, pyrophyllite and CaCl₂ as main raw materials. The suitable burning temperature and the micro-morphology of the cement were studied by XRD, SEM-EDS, etc.. The results show that the optimum burning temperature of the cement is in the range of 1200-1350°C and the composition of cement mineral is alinite with few C₁₁A₇·CaCl₂. The content of C₁₁A₇·CaCl₂ reduced gradually with the increase of burning temperature. Alinite decomposes to form alite (C₃S) at the temperature of 1400°C. The micro-morphology of the cement sample burned at 1350°C is a sinter with high porosity in tri-dimensional network construction, while alinite appears as an irregular polyhedron with twin crystal line on the surface.