A Thermogravimetric study of the alunites of sodium, potassium and ammonium

Frost, Ray L., Wain, Daria L., Wills, Rachael-Anne, Musumeci, Anthony W., & Martens, Wayde N. (2006) A Thermogravimetric study of the alunites of sodium, potassium and ammonium. Thermochimica Acta, 443(1), pp. 56-61.

View at publisher


Thermogravimetry in tandem with mass spectrometry has been used to characterise the thermal decomposition of synthetic alunites of potassium, sodium and ammonium. Three mechanisms of decomposition are observed a) dehydration b) dehydroxylation c) desulphation. The thermal decomposition of the three alunites is different. For NH4-alunite, an additional process of de-ammoniation is observed which occurs simultaneously with dehydration. Dehydroxylation takes place in a series of four steps. De-sulphation occurs for K-alunite at 680 degrees C in a single step in comparison with Na and NH4 alunites where de-sulphation is observed in a series of four steps. The temperature of desulphation is cation dependent. The thermal decomposition is not completed until around 800 degrees C.

Impact and interest:

21 citations in Scopus
17 citations in Web of Science®
Search Google Scholar™

Citation counts are sourced monthly from Scopus and Web of Science® citation databases.

These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.

Citations counts from the Google Scholar™ indexing service can be viewed at the linked Google Scholar™ search.

Full-text downloads:

470 since deposited on 23 Mar 2006
13 in the past twelve months

Full-text downloads displays the total number of times this work’s files (e.g., a PDF) have been downloaded from QUT ePrints as well as the number of downloads in the previous 365 days. The count includes downloads for all files if a work has more than one.

ID Code: 3764
Item Type: Journal Article
Refereed: Yes
Additional Information: This paper is one of a series of papers on alunites and jarosites. The interest in such minerals rests with their possible identification on the planet mars. Such minerals on only formed from solution. The paper reports the stability of a series of alunites.
Keywords: alunite, natroalunite, ammonioalunite, jarosite, thermogravimetry, sulphate
DOI: 10.1016/j.tca.2005.12.019
ISSN: 0040-6031
Subjects: Australian and New Zealand Standard Research Classification > CHEMICAL SCIENCE (030000) > INORGANIC CHEMISTRY (030200)
Divisions: Past > QUT Faculties & Divisions > Faculty of Science and Technology
Copyright Owner: Copyright 2006 Elsevier
Copyright Statement: Reproduced in accordance with the copyright policy of the publisher.
Deposited On: 23 Mar 2006 00:00
Last Modified: 29 Feb 2012 13:23

Export: EndNote | Dublin Core | BibTeX

Repository Staff Only: item control page