Abstract
The zeta potential is a measure of electric potential at the mineral-electrolyte interfaces. The zeta potential of natural sandstones depends on mineralogy, electrolyte pH, concentration, composition, amount of dissolved CO2, and temperature. We report for the first time the zeta potential measured on clayey sandstone comprising quartz, kaolinite, illite, albite and microcline saturated with NaCl solutions at supercritical CO2 conditions. Our results demonstrate that zeta potentials in clayey sandstone samples at supercritical CO2 conditions are significantly different from similar measurements conducted under ambient conditions and from those obtained with clean sandstones. Supercritical CO2 zeta potential remains negative but is influenced by clays and feldspars due to their significant presence and exposure to large pores, which yields less negative zeta potential compared to quartz, under identical conditions. Our results have significant implications to natural subsurface systems such as CO2 geo-sequestration sites, aquifers, geothermal sources and hydrocarbon reservoirs.
Original language | English |
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Article number | e2022GL099277 |
Number of pages | 10 |
Journal | Geophysical Research Letters |
Volume | 49 |
Early online date | 8 Aug 2022 |
DOIs | |
Publication status | Published - 16 Aug 2022 |
Bibliographical note
Open Access via the Wiley AgreementMiftah Hidayat was supported by the Aberdeen-Curtin PhD studentship. David Vega-Maza is funded by the Spanish Ministry of Science, Innovation and Universities (“Beatriz Galindo Senior” fellowship BEAGAL18/00259). Abbie McLaughlin from School of Natural and Computing Sciences and John Still from the School of Geoscience, University of Aberdeen are acknowledged for their assistance in the XRD and SEM analyses.
Data Availability Statement
Detailed information on rock sample preparation and petrophysical characterization is available for download in the Supporting Information S1. Summarized experimental data of San Saba sandstone in this study is available for download at https://doi.org/10.5281/zenodo.6477225.Keywords
- Zeta potential
- Intact natural sandstone
- Carbonated NaCl solutions
- Supercritical CO2 conditions
- Effect of clays
- Streaming potential method