Calcium-barium sulfo-ferritealuminate series minerals

Abstract

Based on the dominant mineral in barium-bearing sulfoaluminate calcium cement C2·75B1·25A3S¯, the calcium-barium sulfo-ferritealuminate series minerals were synthesised by replacing Al3+ with a different equivalent of Fe3+. The microstructure was investigated by means of X-ray diffraction, dynamic thermal analysis/thermogravimetric analysis, scanning electron microscopy–energy dispersive spectroscopy (SEM–EDS). The results indicated that the optimal molar composition of Fe3+ ions was from 0·5 to 1·7. The optimum composition was C2·75B1·25A1·5Fe1·5S¯. At this level, the strength at 1, 3 and 28 days could reach 64, 77·75 and 86·62 MPa, respectively.