How do Zeolites Work?
The basic molecular structure of a zeolite is a tetrahedron or pyramid, formed by silicon oxides (SiOn). The tetrahedron has one silicon atom in the center and oxygen at each of the corners. The tetrahedral zeolites are linked together by oxygen atoms. Linked zeolites form pores, the size of which are determined by how many zeolite molecules are linked together.
Depending of the number of linkages and which alkali ions are present in the crystal structure, several types of zeolites are formed, all with different pore sizes. The size of the pores also determines which VOC’s can be adsorbed.
Munters Zeol uses a mixture of hydrophobic zeolites with different pore sizes. This mixture allows a wide range of organic solvents to be adsorbed. In fact, most commercially available solvents are adsorbed by these hydrophobic zeolites.
A VOC is attracted and held in the zeolite pore by a weak attractive force. This weak physical attractive force between chemically neutral compounds is known as the van der Waals force. The VOC will remain in the pore until it heated, at which time the VOC will be released from the zeolite into the air.
When VOC laden air flows past zeolite molecules, the zeolite acts as a reverse filter or molecular sieve, capturing the compounds which are able to adsorb and allowing the compounds that are too large to flow past.