Quantification of a mixture of synthetic alite and belite by the Rietveld method

Alite and belite are the main components in ordinary portland cement. The quantification by X-ray diffraction methods is very difficult due to the wide range of overlapping reflections, The presented investigations deal with the quantification by fullprofile refinement, To get good structure data of alite and belite both were synthesized in a laboratory furnace at 1400 degrees C, Their chemical composition was the same as that of alite and belite of technically produced cement clinker (modified composition proposed by Taylor 1990 [1]. X-ray investigation of alite shows best fits to the monoclinic superstructure published by Nishi & Takeuchi (1985) [2]. Belite could be described by the structure data of Josf ef al, (1977)[3], Both structures were refined by the Rietveld PC software of Wiles and Young modified by Howard. Afterwards synthetic alite and belite were mixed in different ratios and quantified by the same software. Three different mixtures show a smaller deviation from the input than 1 wt.%.