Zeolite as a raw material to the AAC production

Abstract

Natural zeolites have a long history as a precious raw material in various fields-in catalysis, environmental protection (as sorbents), in agriculture (in fertilizers), as well as in everyday life (as ingredients of detergents). In the last two decades, the possibility of using them in the building material technology began to be taken into account. The paper considers several ways of application of natural clinoptillolite in the autoclaved aerated concrete (AAC) production. Investigations concern the possibility of zeolite dosing as a cement substitute, part of the binder (raw material in the form of a mixture with blast furnace slag), additive to a sand slurry, and a partial substitute of gypsum (used in the AAC recipe). The testing program includes thermal analysis (TG/DTA), phase composition (X-ray powder diffraction), microscopic observation (scanning electron microscope/energy dispersive X-ray spectroscopy), and strength properties of samples autoclaved under existing industrial conditions. The results summary complements the benefits of using zeolite in AAC technology. K E Y W O R D Sautoclaved aerated concrete, hydration products, natural zeolite