Continuous hydrothermal synthesis of inorganic nanopowders in supercritical water: Towards a better control of the process

A hydrothermal synthesis process working in supercritical conditions (T > 374 °C, P > 22 MPa) and in a continuous mode has been developed for inorganic nanopowder synthesis. This paper presents a review of the past 5 years of research conducted on this process. Numerous materials (oxides: ZrO2, TiO2, Fe2O3…, ferrites: Fe2CoO4…, or BaZrO3) were obtained with specific features. Some technical issues have been solved, that are presented here. Heat transfer was studied, leading to a more efficient design of the reactor. Future developments have been examined through process engineering, in which our group is engaged, especially through CFD modelling.

Graphical abstractA hydrothermal synthesis process working in supercritical conditions and in a continuous mode has been developed for inorganic nanopowder synthesis since 2001. This paper proposes a survey of all the research completed in our group for the fabrication of nanomaterials, and presents the evolution and the improvements brought to the process.Figure optionsDownload full-size imageDownload as PowerPoint slide