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NATURAL ZEOLITES IN THE WATER TREATMENT PROCESS
applied in practice for a long time. New identification methods
have contributed to the fact that in the last thirty years, over 1,000
significant cases of the occurrence of more than 50 types of
zeolites
in 40 countries have been recorded.
In the 1980s, a deposit of natural zeolite with a high content of
zeolitic material – clinoptilolite – was found in Nižný Hrabovec in
the region of the East Slovakia neovolcanites.
Natural zeolites were formed by the long-lasting effect of mineral
alkaline solutions on various petrographic types of rocks of different
ages at increased temperatures. It is not surprising that deposits
of these aluminium silicates are located near hot mineral springs
or volcanic craters. The environment in which they were formed
reflects their structure and chemical composition. In a natural
environment zeolites do not occur in a pure state but usually
together with other minerals and rocks. Each deposit contains
rocks with a specific mineralogical structure. This fact explains the
importance of comprehensive research focused on the properties of
natural zeolites and options for their use [1].