Modified desilicated natural zeolite as catalyst for Knoevenagel reaction

Abstract

Natural zeolite (NaZ) has wide range of usage in agriculture and waste water treatment. However, its application as catalyst has not been widely studied. In this research, natural zeolite was modified its property and applied as base catalyst in the Knoevenagel reaction. The modification was done by desilication in alkaline solution at different temperature followed by ion exchanged with calcium and barium ions of alkaline earth metal. The natural zeolite obtained characterized with XRD showed that desilication results in lowering crystallinity of zeolite crystal while FT-IR showed Si/Al ration of the zeolite framework decrease showing the increase of Al in the framework. The catalyst produced was then tested in Knoevenagel reaction and analyzed by gas chromatography (GC) which showed that barium exchanged desilicated NaZ is more active and highly selective than calcium exchanged NaZ due to its higher basicity.