General features of mineral substance high-temperature conversion

Functional areas (stages): low-, medium-, and high-temperature, are established in accordance with cyclic changes of composition, structure, and physicochemical properties of minerals (inorganic compounds) over a wide heat treatment temperature range. In the low-temperature region (<0.3Tm) pyrogenetic processes are of governing importance causing dissociation of thermally active compounds and formation of pseudomorphic minerals (phases) and nanostructures with high specific surface, porosity, and physicochemical activity. At moderate temperatures (normally 0.3 – 0.8Tm) a ceramic structure is formed, providing sintered products with the maximum level of physicochemical properties. The high-temperature region (>0.8Tm) has thermal aging, discriminatory pyroselection of components, and thermal breakdown of ceramic material structure.