The Kinetics of Thermal Decomposition of Nickel Formate Dihydrate in Air

Abstract

Differential thermal analysis-thermogravimetry (DTA-TG), and electron scanning microscopy (ESM) were used to study the decomposition of nickel formate dihydrate in air. The results showed that the decomposition pro- ceeds in two successive TG steps, the first is due to dehydration and the second is due to decomposition of the anhydrous salt and oxidation to form NiO. Ki- netic analysis of the isothermal TG data of the two steps in view of various het- erogeneous solid-state reaction models showed that the dehydration step is hest described by phase boundary models whereas the second step reactions are best described by the branching nucleation model. The changes in morphology that accompany the thermal decomposition of samples as revealed by ESM mi- crographs, were described and the kinetics and mechanism of the thermal de- composition reaction were discussed.