Effect of CO2 Partial Pressure on the Thermal Decomposition Kinetics of Zinc Carbonate Hydroxide (TECHNICAL NOTE)

In this work, the effect of carbon dioxide partial pressure on the calcination kinetics of high purity zinc carbonate hydroxide has been studied. Non-isothermal analysis has been performed on samples at different CO2 partial pressures by TGA and DTA. It has been found that the calcination behaviour of this material corresponds to the shrinking core model and the reaction mechanism is phase boundary controlled. The calcination reaction of zinc carbonate hydroxide starts at 240 oC. Increasing the carbon dioxide partial pressure can result in an increase in the reaction start temperature of up to 30˚C. The activation energy for the reaction is calculated as 180 ± 5 kJ/mol at significant CO2 partial pressures.