Kinetics of Chlorination-Volatilization Reaction of Heavy Metals from Solid Waste and Dust

摘要

Various pyrometallurgical processes for secondary ash and dust treatment, such as secondary melting and pelletization, have been proposed for the volume reduction, detoxification and efficient recovery of valuable resources. In order to reduce the heavy metal concentration in residues, a better understanding of kinetic features of the chlorination-volatilization reaction is necessary. In the previous thermodynamics study on oxychlorides employing CALPHAD approach, the motive force for the chlorination-volatilization reaction and settlement of optimized thermodynamics parameters have been conducted. The present work places emphasis on the kinetic aspects including investigation on reaction mechanism and estimation of rate-limiting steps.