Skip to Main Content
Skip Nav Destination
GEOREF RECORD

In situ time resolved synchrotron powder diffraction study of mordenite

Annalisa Martucci, Michele Sacerdoti, Giuseppe Cruciani and Chiara Dalconi
In situ time resolved synchrotron powder diffraction study of mordenite
European Journal of Mineralogy (June 2003) 15 (3): 485-493

Abstract

The step by step thermal dehydration process of the zeolites mordenite from Pashan (Poona, India) (Na (sub 3.51) K (sub 0.14) Ca (sub 1.89) Mg (sub 0.09) Sr (sub 0.01) )[Fe (super 3+) (sub 0.03) Al (sub 7.40) Si (sub 40.53) O (sub 96) ] . 27.26H (sub 2) O, has been studied in situ by synchrotron powder diffraction. The time-resolved experiment was performed using a translating imaging plate system. The structure refinements by full profile Rietveld analysis were performed in the Cmcm space group in the temperature range from 25 to 830 degrees C. The results of structure refinements indicate that the slight cell-volume contraction ( approximately 1.9%) is related to the release of water molecules from the channels: above 375 degrees C, the water loss lead to an enlargement of the 8-membered ring parallel to [010], which occurred by a flattening of T3-O9-T3 and T4-O4-T3 bridges. The dehydration process is reflected not only in the content of water molecules in the zeolite channel, but also in the temperature behaviour of the unit cell parameters. The cell parameters b and c decreased regularly as the temperature rose, whereas a decreased up to 400 degrees C then increased up to 630 degrees C, and finally decreased until the end of experiment. The removal of water molecules was accompanied by a spreading of the initial Ca sites into many positions bonded to the framework oxygens. The increased interaction with the framework oxygens of Ca sites was intimately related to the distortion of the 12-ring which is in turn related to the lengthening of the a cell parameter.


ISSN: 0935-1221
EISSN: 1617-4011
Serial Title: European Journal of Mineralogy
Serial Volume: 15
Serial Issue: 3
Title: In situ time resolved synchrotron powder diffraction study of mordenite
Affiliation: Universita di Ferrara, Dipartimento di Scienze della Terra, Ferrara, Italy
Pages: 485-493
Published: 200306
Text Language: English
Publisher: Schweizerbart'sche Verlagsbuchhandlung (Naegele u. Obermiller), Stuttgart, Federal Republic of Germany
References: 28
Accession Number: 2003-055033
Categories: Mineralogy of silicates
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus. incl. 4 tables
Country of Publication: Germany
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute.
Update Code: 200318
Close Modal

or Create an Account

Close Modal
Close Modal