The role and implications of bassanite as a stable precursor phase to gypsum precipitation.
Science
; 336(6077): 69-72, 2012 Apr 06.
Article
en En
| MEDLINE
| ID: mdl-22491851
ABSTRACT
Calcium sulfate minerals such as gypsum play important roles in natural and industrial processes, but their precipitation mechanisms remain largely unexplored. We used time-resolved sample quenching and high-resolution microscopy to demonstrate that gypsum forms via a three-stage process (i) homogeneous precipitation of nanocrystalline hemihydrate bassanite below its predicted solubility, (ii) self-assembly of bassanite into elongated aggregates co-oriented along their c axis, and (iii) transformation into dihydrate gypsum. These findings indicate that a stable nanocrystalline precursor phase can form below its bulk solubility and that in the CaSO(4) system, the self-assembly of nanoparticles plays a crucial role. Understanding why bassanite forms prior to gypsum can lead to more efficient anti-scaling strategies for water desalination and may help to explain the persistence of CaSO(4) phases in regions of low water activity on Mars.
Texto completo:
1
Base de datos:
MEDLINE
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Science
Año:
2012
Tipo del documento:
Article
País de afiliación:
España