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

Magnesium silicate hydrate (M & horbar; S & horbar; H) cement has many excellent properties, but its resistance to corrosion by SO42- and Cl- has not been investigated. In this study, M & horbar; S & horbar; 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 & horbar; S & horbar; H gel in M & horbar; S & horbar; H cement. The pH value of the M & horbar; S & horbar; 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 & horbar; S & horbar; H cement reached 46.7 MPa. In water bath curing, the porosity was 8.3304%, and the average pore diameter was 8.526 m(2)/g. The retention coefficients of the M & horbar; S & horbar; H cement were 0.84 and 0.93 in Cl- and SO42- solutions, showing good resistance to sulfate and chloride corrosion.