The non-isothermal decomposition process of anhydrous nickel nitrate under air atmosphere was investigated. The kinetic analysis of decomposition process was performed using Friedman (FR), Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) isoconversional methods. The kinetic model was determined by the Malek's method. The composite differential method I was used for checking the established reaction model. It was found that the value of E-a calculated by composite differential method (E-a = 147.1 kJ mol(-1)) represents the medium value between the values of the apparent activation energy calculated by FR (E-a,E-FR = 152.8 kJ mol(-1)) and FWO (E-a,E-FWO = 143.1 kJ mol(-1)) methods. Using two special functions (y(alpha) and z(alpha)), it was found that the two-parameter autocatalytic model (Sestak-Berggren (SB) kinetic model) with kinetic exponents M = 0.23 and N = 1.14 is the most adequate one to describe the decomposition kinetics of the studied system at various heating rates. The obtained non-isothermal differential conversion curves from the experimental data show the results being accordant with those theoretically calculated. It was concluded that the SB kinetic model can be used for a quantitative description of non-isothermal decomposition process of anhydrous nickel nitrate which involves the partially overlapping nucleation and growth phases.
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