Non-isothermal decomposition of nickel acetate tetrahydrate

Abstract

Non-isothermal decomposition of nickel acetate tetrahydrate was studied by means of thermogravimetry (TG), differential thermal analysis (DTA) and differential scanning calorimetry (DSC) from ambient temperature up to 500°C. The parent salt was found to commence dehydration near 80°C giving the anhydrous nickel acetate, which on further heating produced basic nickel acetate. Decomposition took place above 250°C with the formation of nickel carbide (Ni 3C), which, together with the basic acetate, decomposed to a mixture of NiO and nickel metal. Kinetic parameters (Δ E and ln A) and thermodynamic parameters (Δ H and C p) are given for the dehydration and decomposition processes. Infrared spectroscopy and X-ray powder diffractometry were used to identify the solid decomposition products while gas chromatography was employed to identify the volatile decomposition products (acetic acid, acetone, CO 2, and trace amounts of CO, ethyl acetate and propionic acid). The distribution of these volatile products was found to be influenced by the prevailing atmosphere (N 2 or O 2).