What is Zeolite and what are its Mineral Properties?
Without getting too technical with respect to zeolite, it is a natural occurring mineral. It is a microporous aluminosilcate which has the properties of adsorption. That is to say, it acts as a microfi lter, or sieve, which allows some molecules to pass through while capturing other desired molecules within its cube-like structure. The term molecular sieve refers to a particular property of these materials, i.e., the ability to selectively sort molecules based primarily on a size exclusion process. This is due to a very regular pore structure of molecular dimensions. The maximum size of the molecular or ionic species that can enter the pores of a zeolite is controlled by the dimensions of the channels. These are conventionally defi ned by the ring size of the aperture, where, for example, the term „8-ring“ refers to a closed loop that is built from 8 tetrahedrally coordinated silicon (or aluminum) atoms and 8 oxygen atoms. In layman’s terms, the capturing of targeted molecules is therefore size dependent. Similar to a fi sh net, some zeolites will capture large molecules and others small molecules. Up to forty (40) different zeolite structures are known to naturally occur with each one having a particular and unique structure.
With the “fi lter mechanism” now understood, we now can discuss where zeolite can be used in commercial environments for particular applications where fi ltering or molecular capturing is desired ; Environmental remediation applications for air, water and soil :
- Radioactive waste containment applications
- Mercury removal from coal burning utilities’ and other industries’ stack gases
- Purifi cation (removal of hydrogen sulfi de and water) of natural gas streams
- Specialty sorbents and catalyst applications in processing
- Water treatment and sewage applications
- Lightweight Zeolite Concretes for the completion of oil and gas production
wells and for construction applications