Zeolite is a hydrous alumino-silicate chemical compound with sodium, potassium and barium cations. In general, zeolite has a unique molecular structure, where the silicon atoms are surrounded by 4 oxygen atoms to form a kind of network with a regular pattern. In some places in this network, Silicon atoms are replaced by Aluminum atoms, which are only coordinated with 3 Oxygen atoms. This Aluminum atom only has a charge of 3+, while Silicon itself has a charge of 4+. The presence of aluminum atoms as a whole will cause Zeolite to have a negative charge. This negative charge is what causes Zeolite to be able to bind cations. Zeolite is also often referred to as 'molecular sieve' / 'molecular mesh' (molecular sieve) because zeolite has molecular sized pores so it is able to separate/filter molecules of a certain size. Zeolite has several properties, including: easily releasing water due to heating, but also easily rebinding water molecules in humid air. Because of these properties, zeolite is widely used as a drying agent. Besides that, zeolite also easily releases cations and is replaced with other cations, for example zeolite releases sodium and is replaced by binding calcium or magnesium. This property also causes zeolite to be used to soften water. Zeolite with a certain cavity size is also used as a catalyst to convert alcohol into hydrocarbons so that the alcohol can be used as gasoline.
