Decomposition processes of nickel hydroxide

The dehydration processes of nickel hydroxide were studied by means of thermogravimetry in a temperature range from 300 to 900 K. The kinetics of the low-temperature dehydroxylation (≈300–600 K) was studied under non-isothermal conditions. A model-free method was used to calculate the activation energy and to analyze the stepwise checking; the non-linear regression method was applied to calculate the kinetic parameters of multi-stage decomposition reactions. The features of the dehydroxylation kinetics for the multi-stage process are explained by the formation and decomposition of hydrogel and xerogel phases.