Hydrothermal solidification of zeolite/tobermorite composites

Abstract

Novel zeolite/tobermorite composites were prepared by hydrothermal treatment of a powder-compact consisting of mordenite and slaked lime. Tobermorite formed after the hydrothermal process due to the reaction of mordenite and slaked lime. The bending strength after the hydrothermal process was more than 7 MPa. X-ray diffraction analysis results showed that mordenite remained after the hydrothermal treatment, resulting in the existence of inherent micropores of mordenite in the composites. The composites exhibited a broad mesopore size distribution of more than 6 nm. The improvement in strength, mesopore formation, and specific surface area of the composites depended on the amount and size of the tobermorite that was formed.