A Review of the Mechanisms of Decomposition of Solids and Their Relevance to Extractive Metallurgical Processes

This review examines the progress which has been made in understanding the chemical reactions and the microstructural changes which occur during the decomposition of solids. A number of common product morphologies are described, and the relationships between reaction mechanisms, the product microstructures and kinetics are explained. From the analysis of a number of systems it is argued that changes in product morphology take place when changes occur in the relative rates of the chemical reactions and mass transport processes on or in the product or original solids. The factors affecting these transitions and ways of control ling product microstructure are discussed.