Resistance of Magnesium Silicate Hydrate Cement to SO42− and Cl− Corrosion

Abstract

Magnesium silicate hydrate (M─ S─ H) cement has many excellent properties, but its resistance to corrosion by SO42− and Cl− has not been investigated. In this study, M─ S─ H cement was prepared from light burned magnesia powder obtained from magnesite tailings, and its erosion resistance for SO42− and Cl− was investigated. X-ray diffraction (XRD) and flight test instrumentation requirements (FTIR) showed a signal characteristic of M─ S─ H gel in M─ S─ H cement. The pH value of the M─ S─ H cement was in the range of 8–9, first increasing and then decreasing as hydration time increased. The 28-day compressive strength of the M─ S─ H cement reached 46.7 MPa. In water bath curing, the porosity was 8.3304%, and the average pore diameter was 8.526 m2/g. The retention coefficients of the M─ S─ H cement were 0.84 and 0.93 in Cl− and SO42− solutions, showing good resistance to sulfate and chloride corrosion.