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Comparative study of coral conversion, Part 3: Intermediate products in the first half an hour

Macha, Innocent Jacob and Charvillat, Cédric and Cazalbou, Sophie and Grossin, David and Boonyang, Upsorn and Ben-Nissan, Besim Comparative study of coral conversion, Part 3: Intermediate products in the first half an hour. (2016) Journal of The Australian Ceramic Society, 52 (1). 177-182. ISSN 0004-881X

(Document in English)

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Different methods to produce calcium phosphate materials have been well established and are currently used by both scientific and industrial community. While other new and more economical production techniques are under development, the actual reactions mechanisms involve in these techniques are not well understood. Understanding what really happen during reaction will pave a way to tune the final product for well-defined morphology and purity. We focused into improving in-depth understanding of the reaction mechanisms and the intermediates products participating in the reaction of coralline materials with orthophosphoric and ammonium phosphate solutions under mechano-chemical reaction technique. The results suggest that within 30 minutes of reaction under ammonium phosphate solution only HAp phase is produced through solid-state iron exchange reaction. On the other hand, under orthophosphoric acid solution, intermediate phases such as octacalcium phosphate (OCP) and monetite form and convert to hydroxyapatite HAp at different times. Other phase that formed as an intermediate was identified as brushite. It was also observed that pH plays a big role in the formation of these phases due to their different pH stability. The results also confirm our previous hypothesis that under orthophosphoric acid phosphate solution the reaction mechanism is dissolution-recrystallization while under ammonium phosphate solution is solid-state topotactic ion exchange reaction mechanism. It is envisaged that there are possibilities of the formation of intermediate products within or before the first 5 minutes of reaction.

Item Type:Article
Additional Information:hanks to The Australian ceramic society. The definitive version is available at http://austceram.com/ The original PDF of the article can be found at http://austceram.com/volume-52-number-1-2016/
HAL Id:hal-01468002
Audience (journal):International peer-reviewed journal
Uncontrolled Keywords:
Institution:French research institutions > Centre National de la Recherche Scientifique - CNRS (FRANCE)
Université de Toulouse > Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
Université de Toulouse > Université Toulouse III - Paul Sabatier - UT3 (FRANCE)
Other partners > University of Technology, Sydney - UTS (AUSTRALIA)
Other partners > Walailak University - WU (THAILAND)
Laboratory name:
Deposited On:15 Feb 2017 08:23

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