Chemical interaction of calcium oxide and calcium hydroxide with CO2 during mechanical activation

The reactions of CaO and Ca(OH)(2) with CO2 during mechanical activation are studied by IR spectroscopy, x-ray diffraction, and thermal analysis. The results indicate that the earlier described extensive sorption of CO2 by Ca-containing silicates during grinding is not related to the formation of CaO or Ca(OH)(2). Mechanical activation in CO2 converts calcium oxide to amorphous CaCO3 and calcium hydroxide to calcite, whereas Ca-containing silicates under such conditions homogeneously dissolve CO2 to form a material similar to analogous carbonate-containing silicate glasses.