科研成果详情

The kinetics of thermal dehydroxylation of aluminuous goethites [1] synthesised from a ferrous salt has been re-examined using the general reaction order kinetic law. The utilised data processing was based on the procedures employed by dissolution kinetics. Recalculation of the activation energies E_A of the dehydroxylation yielded the values 130, 132, 128, and 123 kJ mol⁻¹ for pure goethite, goethite with 10, 20, and 30 mol% Al substitution, respectively. The values of E_A are in a good agreement with those given for goethite in literature. The E_A values are linearly related with the chemically bound excess H₂O/OH⁻ in the crystal lattice that is apparently influenced by Al substitution.