Crystallisation of a highly metastable hydrated calcium pyrophosphate phase

Pierre Gras (1) , Sébastien Teychené (2) , Christian Rey (1) , Cédric Charvillat (1) , Béatrice Biscans (2) , Stéphanie Sarda (1) , Christèle Combes (1)

1 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux
2 LGC - Laboratoire de Génie Chimique

A simple and fast synthesis method was set up to obtain pure hydrated calcium pyrophosphate (CPP)phases of biological interest. This work focused on a specific phase synthesised at 25 uC and pH 4.5 in a stirred tank reactor. Powder X-ray diffraction, FTIR spectroscopy, scanning electron microscopy and thermogravimetric analyses revealed that the phase is unknown but presents similarities with a monoclinic tetrahydrated CPP phase (Ca2P2O7?4H2O, m-CPPT b phase) synthesised under the same conditions of pH and temperature. Characterisation of the unreferenced phase (u-CPP) has been performed, especially to better identify its composition, structure and stability, as well as its possible relation to the m-CPPT b phase or to other hydrated CPP phases.

Mots clés: Hydrated calcium pyrophosphate; Metastable u-CPP

Domaines: Cristallographie

Pierre Gras, Sébastien Teychené, Christian Rey, Cédric Charvillat, Béatrice Biscans, et al.. Crystallisation of a highly metastable hydrated calcium pyrophosphate phase. CrystEngComm, 2013, vol. 15, pp. 2294-2300. ⟨10.1039/C2CE26499D⟩. ⟨hal-00917720⟩