Study of thermal evolution of porous hematite by emanation thermal analysis

Emanation thermal analysis (ETA) was used for the characterization of surface and porosity annealing of acicular porous hematite samples in the temperature range from 20 to 600 °C under in situ conditions of heating in air flow. Two hematite samples with different surface areas (85 and 44 m2 g−1, respectively) were prepared by thermal decomposition of goethite using constant rate thermal analysis (CRTA) equipment. ETA results characterizing the thermal evolution of the porous hematite samples were compared with surface area determined by B.E.T. method, transmission electron micrographs and crystallite size determined by XRD.