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Zeolites are a member of the class of materials known as molecular sieves. ...
Currently there are forty zeolites found in nature and more than one hundred and fifty others have been synthesised. The formation of zeolites are dependant on a number of specific conditions which must be favourable, such as temperature, pressure, pH, the type of silicon or aluminium source and the type and concentration of salts present. ...
However, the zeolites produced in this manner are usually widely dispersed and therefore not suitable for use in industry. ... Beds that are rich in zeolites may be hundreds of meters thick and beds of tuff that have been mostly converted into zeolites can reach thicknesses of several kilometers. ... Rocks high in silica tend to produce zeolites with a high silica content, and aluminous zeolites are often associated with silicon deficient rocks. In natural deposits of zeolites there may be more than one species present and there is sometimes evidence of the gradual replacement of one species with another, rather than simple co-crystalisation. ...
It wasnt until the early 1940s that scientists first began to attempt to synthesise zeolites. Mineralogists interested in the stability of relationships between zeolites and other minerals made the first syntheses.
The methods used in industry to produce zeolites are dependant on the specific requirements of the final use of the product, and it is common to have to technically alter the product. ... In industry, zeolites may be synthesised either from hydrogels or clay minerals. ...
Zeolites may also be synthesised from clay minerals. ...
There are many uses in industry for both natural and synthetic zeolites. Naturally occuring zeolites are often contained by other minerals (eg Fe2+ and quartz) and it is for this reason that they are excluded from many of the commercial applications of zeolites in which uniformity and purity are essential.
Approximate Word count = 1354
Approximate Pages = 5.4
(250 words per page double spaced)
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