Hydrothermal synthesis of flower-like ammonium illite constructed by nanosheets from coal series kaolin

Ammonium illite with hierarchical flower-like structure was synthesized from coal series kaolin under hydrothermal condition at 300 °C for 1 h. The product was characterized by X-ray powder (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that the flower-like ammonium illite is constructed by nanosheets with thickness of ca. 20 nm and a diameter of ca. 400 nm. New phase was obtained by calcination of above product at 700 °C for 2 h, and the flower-like morphology was retained after calcination. Furthermore, the specific surface area of ammonium phase powder was calculated to be 197.2 m2/g by BET measurement. The possible formation mechanism for flower-like ammonium illite was proposed and discussed.

► Fist time, nanolayer and flower-like material were synthesized from kaolin.
► The raw material is cheap and easily available in China.
► The process of this method is simple and fast.
► The product has relatively high specific surface area of 197 m2/g.