Chemical Durability of Synthesized Sphene

The chemical durability of synthesized sphene, using CaCO3, TiO2 and H2SiO3 as raw materials by solid-state reaction, was researched by means of X-ray diffraction(XRD), scanning electron microscope(SEM) and atom absorbing spectrum(AAS). The results indicate that the synthesized sphene has a good chemical durability in the aqueous solution whose ph value is 5-9, the temperature and ph of the solution have important influences to its chemical durability in 1-21 days. The nominalized leach rate of Ca2+(42 d) is higher than Ti4+ about 2 orders of magnitude.When the ph is 7 at 90 degree C, the nominalized leaching rate of Ca2+(42 d) and Ti4+(42 d) are 3.33 x 10-3 and 1.33 x 10-5 g·m-2·d-1, respectively. When the ph is 7 at 25 degree C, the nominalized leach rate of Ca2+(42 d) and Ti4+(42 d) are 1.52 x 10-3 and 3.05 x 10-5 g·m-2·d-1, respectively. The nominalized leach rate of Ca2+(42 d) is 7.71 x 10-2 g·m-2·d-1, when the ph is 3 at 25 degree C. (authors)