Original paper

Thermal behaviour of analcimes from two different genetic environments

Giampaolo, Ciriaco; Lombardi, Gianni

European Journal of Mineralogy Volume 6 Number 2 (1994), p. 285 - 290

18 references

published: Mar 31, 1994
manuscript accepted: Dec 14, 1993
manuscript received: Jul 5, 1993

DOI: 10.1127/ejm/6/2/0285

BibTeX file

ArtNo. ESP147050602012, Price: 29.00 €

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Abstract

Abstract: Hydrothermal analcimes (H-type) and leucite-derived analcimes (X-type) from different Italian localities have very similar XRD patterns but different thermal behaviours. Dehydration of the H-type analcime gives a DTA peak between 350° and 370°C, whereas the X-type yields a wide band between 235° and 320°C. Activation energy in the H-type analcime is 6.9-7.1 kcal/mole, whilst in the X-type it is 5.3 kcal/mole. Such results are of relative value only because they are derived from non-isothermal runs and are strongly affected by the chosen method of calculation. Both DTA and TG methods provide evidence for a difference in the H2O bonding energies within the analcime structure crystallized in different genetic environments.

Keywords

Hydrothermal analcimes (H-type) and leucite-derived analcimes (X-type) from different Italian localities have very similar XRD patterns but different thermal behaviours. Dehydration of the H-type analcime gives a DTA peak between 350° and 370°Cwhereas the X-type yields a wide band between 235° and 320°C. Activation energy in the H-type analcime is 6.9-7.1 kcal/molewhilst in t