THE BINDING CHEMISTRY AND LEACHING MECHANISMS OF HAZARDOUS SUBSTANCES IN CEMENTITIOUS SOLIDIFICATION STABILIZATION SYSTEMS

The chemistry of binding and the mechanisms of leaching of hazardous substances, particularly priority (heavy) metal pollutants, in cementitious stabilization/solidification (S/S) systems are discussed in terms of their bulk and surface states. Particular attention is given to the nature of the surface species and their surface and solution chemistries. Key to understanding the binding and leaching processes in cement is the characterization of the chemical and physical states involved. The available characterization techniques will be outlined and their application to model doped samples will be demonstrated. Recent efforts in the surface bulk, and morphological characterization of model S/S hazardous metal-portland cement systems will be presented with the results summarized in physical and chemical concepts. The ultimate aim of the work is to provide information to provide the understanding necessary for the design of new or improved stabilization and solidification systems and for information needed to mathematically model the leaching. © 1990.