سیده نرجس حسینی

The kinetic studies of aluminothermic reaction between Al and Co3O4 were investigated under non-isothermal conditions using X-ray diffraction (XRD) and differential thermal analysis (DTA). It was found that Co3O4 reacts with Al through a self-sustaining combustion reaction and this reaction involves two steps. First step includes the reduction of Co3O4 to CoO ( ) while the second step involves the reaction of CoO with remaining Al ( ). Mechanical activation of the initial powder mixture decreased the second reduction reaction temperature from 1041 to 869?C. The activation energies of these reduction reactions, calculated using five different model-free methods of Vyazovkin, Tang, Starink, Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) on a conversion fraction of 0.5 were determined to be about 340±5 and 440±7 kJ/mol, respectively.