Solid‐State NMR Studies of the Structure and Reactivity of Metakaolinite

Abstract

Si atoms in various environments, as well as tetra‐, penta‐, and hexacoordinated AI atoms , have been observed in metakaolinite by high‐resolution solid‐state NMR spectroscopy. Their ratios depend upon the calcination temperature. Studies have shown that the most reactive metakaolinite (calcination temperature 480‐500 ° C) is associated with a minimum concentration of hexacoordinate and a maximum concentration of tetra‐ and pentacoordinate Al.