Flow supercritical synthesis of brucite and magnesian T-O, T-O-T phyllosilicates : an opportunity to tune the structure with the solvent composition

Marie Claverie (1, 2) , François Martin (3) , Christel Carême (2) , Christophe Le Roux (3) , Pierre Micoud (3) , O. Grauby (4) , Cyril Aymonier (1)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
2 Imerys Aluminates
3 GET - Géosciences Environnement Toulouse
4 CINaM - Centre Interdisciplinaire de Nanoscience de Marseille

This work presents the synthesis of minerals with a layered structure in supercritical water/ethanol mixtures to decrease the critical coordinates of the solvent regarding water. Depending on the water/ethanol ratio of the solvent, we obtained three different minerals adopting an octahedral brucitic sheet: (1) without a Si-tetrahedral sheet (O); (2) associated with one Si-tetrahedral sheet (T-O); or (3) intercalated between two Si-tetrahedral sheets (T-O-T). We have thus shown that ethanol in a supercritical water/ethanol mixture changes the solubility of silicon with a direct consequence on the formation of the tetrahedral silicon sheets and thus makes it possible to control the structure of the synthesized layered material.

Domaines: Matériaux

Marie Claverie, François Martin, Christel Carême, Christophe Le Roux, Pierre Micoud, et al.. Flow supercritical synthesis of brucite and magnesian T-O, T-O-T phyllosilicates : an opportunity to tune the structure with the solvent composition. Clay Minerals, 2018, 53 (3), pp.497-503. ⟨10.1180/clm.2018.36⟩. ⟨hal-02171728⟩