Biotite dissolution in brine at varied temperatures and CO2 pressures : its activation energy and potential CO2 intercalation

For sustainable geologic CO(2) sequestration (GCS), it is important to understand the effects of temperature and CO(2) pressure on mica's dissolution and surface morphological changes under saline hydrothermal conditions. Batch experiments were conducted with biotite (Fe-end member mica) under...

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Veröffentlicht in:Langmuir : the ACS journal of surfaces and colloids. - 1992. - 28(2012), 41 vom: 16. Okt., Seite 14633-41
1. Verfasser: Hu, Yandi (VerfasserIn)
Weitere Verfasser: Jun, Young-Shin
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2012
Zugriff auf das übergeordnete Werk:Langmuir : the ACS journal of surfaces and colloids
Schlagworte:Journal Article Research Support, U.S. Gov't, Non-P.H.S. Aluminum Silicates Ferrous Compounds Salts brine biotite 1302-27-8 Carbon Dioxide 142M471B3J
Beschreibung
Zusammenfassung:For sustainable geologic CO(2) sequestration (GCS), it is important to understand the effects of temperature and CO(2) pressure on mica's dissolution and surface morphological changes under saline hydrothermal conditions. Batch experiments were conducted with biotite (Fe-end member mica) under conditions relevant to GCS sites (35-95 °C and 75-120 atm CO(2)), and 1 M NaCl solution was used to mimic the brine. With increasing temperature, a transition from incongruent to congruent dissolution of biotite was observed. The dissolution activation energy based on Si release was calculated to be 52 ± 5 kJ mol(-1). By comparison with N(2) experiments, we showed that CO(2) injection greatly enhanced biotite's dissolution and its surface morphology evolutions, such as crack formation and detachment of newly formed fibrous illite. For biotite's dissolution and morphological evolutions, the pH effects of CO(2) were differentiated from the effects of bicarbonate complexation and CO(2) intercalation. Bicarbonate complexation effects on ion release from biotite were found to be minor under our experimental conditions. On the other hand, the CO(2) molecules in brine could get into the biotite interlayer and cause enhanced swelling of the biotite interlayer and hence the observed promotion of biotite surface cracking. The cracking created more reactive surface area in contact with brine and thus enhanced the later ion release from biotite. These results provide new information for understanding CO(2)-brine-mica interactions in saline aquifers with varied temperatures and CO(2) pressures, which can be useful for GCS site selection and operations
Beschreibung:Date Completed 06.03.2013
Date Revised 21.11.2013
published: Print-Electronic
Citation Status MEDLINE
ISSN:1520-5827
DOI:10.1021/la3028995