Zeolite modification implies an irreversible change, unlike ion exchange or adsorption. There are a number of different ways that zeolites can be modified. The framework of the zeolite can be modified by synthesizing zeolites with metal cations other than aluminum and silicon in the framework. The framework of the zeolites can be modified by dealumination to increase the silica and increase the hydrophobic nature of the zeolite. There are many proprietary methods to modify zeolites that impart unique characteristics to them.
Zeolites are available as powders or as formed products such as extrudates.
Zeolites, like other solids, are safe to handle and are easy to use in a variety of reactors. During the 1930's, R. Barrer and J. Sameshima did extensive work in zeolite synthesis. In 1948, Richard Barrer first produced a synthetic zeolite that did not have a natural counterpart. At approximately the same time, Milton made the first materials that had no natural counterpart such as zeolite A. 12. New natural zeolites are still being discovered, and new synthetic zeolites are being invented in many laboratories around the world.