International Journal of Mineral Processing, Vol.69, No.1-4, 143-155, 2003
Mechanical activation of natural titanite and its influence on the mineral decomposition
Processes induced by mechanical activation of the natural titanite CaTiSiO5 using a laboratory agate mechanical mortar and a planetary mill AGO-3 have been studied. Titanite consumes substantial amounts of atmospheric carbon dioxide during prolonged dry grinding in air. Carbonisation of titanite occurs alongside with its amorphyzation. According to FT-IR spectroscopic data CO2 is present in the ground sample in the form of distorted CO32- groups resulting in the characteristic double band in the 1500-1430 cm(-1) region. Previously similar processes were revealed for Ca and Mg containing silicate gangue minerals such as enstatite MgSiO3, diopside CaMgSi2O6, (a) over circle kermanite Ca2MgSi2O7, and wollastonite CaSiO3. The CO2 content in the ground titanite reached 4.0 and 7.0 wt.% after grinding in the laboratory agate mechanical mortar for 36 and 108 h, respectively. The amount of carbon dioxide consumed due to grinding increases with increasing CaO content in the chemical formula of minerals and correlates with Gibbs free energies of reactions of the crystalline minerals with CO2. The following sequence concerning carbon dioxide sorption ability was revealed: enstatitekennanite