STUDY OF THERMALLY TREATED ZEOLITIC TUFFS OF SERBIA , DEPOSITS "ZLATOKOP" AND "OPĆIŠTE"-BEOČIN

Abstract

Zeolites are a group of natural and synthetic inorganic compounds. They have specific physicochemical properties suitable for industrial application [1,2]. According to their origin, variety of chemical composition, structural characteristics and application, zeolites form a specific group of minerals within the tectosilicates. In sedimentary formations rich in zeolites, the most characteristic minerals that are present are: clinoptilolite/hailandite, chabazite, mordenite, erionite, phillipsite and analcime. The most widespread zeolite of sedimentary origin is represented by the HEU series (clinoptilolite-heylandite). Its general crystal chemical formula is (Na,K,Ca)6Al6Si30O72nH2O.. Based on chemical and X-ray powder diffraction analysis, it is not possible to separate clinoptilolite and hoylandite . This is due to their isostructural nature. To identify these two isostructural minerals, even today, the simplest so-called Mampton's test [3]. Mumpton [4]. The results of X-ray diffraction analysis of thermally treated clinoptilolitic tuffs from the Zlatokop and Beočin deposits will be presented in this paper. The interplane distance values will be shown in the characteristic temperature range from 400oC to 500oC (when the first polymorphic transition occurs). These values characterize the zeolitic tuffs of our deposits in a certain way.