Layered silicates rapid protonation

When clay minerals are treated with dilute acids ( activation process), protons may attack the silicate layers via the interlayer region and exposed edges. Octahedral ions such as AP and Mg are extracted into the interlayer which promotes a rapid decomposition. However, many mont-morillonites resist such a treatment, even when using concentrated acids . Formation of layer defects allows the number of anchoring points for new cations at the surface layer to increase. 

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