Interaction of natural and thermally processed vermiculites with gaseous carbon dioxide during mechanical activation

In the FT-IR spectra, the observed bands attributed to carbonate in the range of 1430-1550 cm− 1 were singlets (for the natural and thermally exfoliated vermiculites) or split (for the heated vermiculite). This effect is likely due to structural breakdown and increased amorphisation created by heating and mechanical activation.