Calcination and partial reduction at temperatures below 1000 degrees C is a primary step in pyrometallurgical extraction of nickel from laterites. Identifying the main reactions that occur during this process and investigating their kinetics provide valuable information on the rates of the reactions and their degree of completion. The main reactions were identified using thermal gravimetric analysis-differential scanning calorimetry (TGA-DSC), X-ray diffraction, and scanning electron microscope energy dispersive spectroscopy (SEM-EDS) tests. Transformation of goethite to hematite, dissociation of lizardite to forsterite and silica, and decomposition of silicate were identified as the main reactions. The kinetic parameters for the three main reactions were obtained using both model-free and model-fitting methods. Comparing the activation energy obtained by the two kinetic approaches, Avrami-Erofeev model was selected as the kinetic model for the aforementioned reactions.