2015) concluded that HCl is able to extract Mg from some clay minerals such as smectites
, this process appeared to not be effective for calcareous soils (as evidenced by no change in Al concentration).
For instance, the numerical simulations predict trioctahedral smectites
and chlorite to be stable across the entire temperature range considered in the model.
Montmorillonite is a 2:1 phyllosilicate that belongs to the group of smectites
and it is the main component of bentonite clay.
The ability of smectites
to incorporate interlayer [H.sub.2]O molecules and the subsequent change in dm have been studied for several decades.
are swelling clay minerals that belong to the family of the phyllosilicates 2:1, which naturally occur in both terrestrial and marine environments  where they often represent the most effective components.
These include acid activation , treatment with cationic surfactants , thermal treatment , pillaring, de-lamination and re-aggregation of smectites
 and grafting of organic compounds .
AEM characterization of phyllosilicates (Table 2) revealed that dioctahedral smectites
are Al-dominant (between 1.88 and 1.97 a.p.f.u.
In fact, smectites
are a clay mineral, more precisely, a 2: 1 type of aluminosilicate characterized by a high cation retention ability and low permeability and swelling.
In the case of Vertisols, the presence of smectites
is responsible for their unique morphological properties, such as the clay content (>30%), shrink-swell activities, presence of slickensides, wedge-shaped peds, and gilgai microrelief.
are a specific type of clay mineral that expands and contracts with adsorbed water.
MI clay cutans typically show a smooth appearance in SEM due to the small crystal size of the dental smectites
and their tangential organisation.