The Kinetics of Spinel Formation of Algerian Halloysite by Differential Thermal Analysis

Abstract

The kinetics of spinel (Al-Si) crystallization from Algerian halloysite (DD1) was investigated using differential thermal analysis. Experiments were carried out on samples between room temperature and 1400• C with constant heating rate from 2 to 20The activation energies measured from isothermal and non-isothermal treatments were 1054.85 and 1140 kJ mol −1 , respectively, for the spinel (Al-Si) formation. The Avrami constant n obtained by the Ligero method and the m parameter obtained by the Matusita method were about 2 for spinel crystallization. This value indicates that the crystallization mechanism of Al-Si spinel phase proceeds by bulk nucleation of the phase formation with a constant number of nuclei and that the three-dimensional growth of crystals is controlled by diffusion.

Modified halloysite nanotubes decorated with Ceria for synergistic corrosion inhibition of Polyolefin based smart composite coatings

“…In the first stage, the first small endothermic peak is seen at around 50 • C, which is water mass loss as seen in the TGA curve. The structural decomposition of Hal is seen at around 492.66 • C due to the de(hydr) oxidization of Hal, as explained earlier in this section (Heraiz et al, 2017).…”