TY - JOUR
T1 - Enhancing Hydrogen Storage Efficiency in Organic-Rich Shales Using Silica Nanofluids
T2 - A Comprehensive Study on Wettability Alteration
AU - Alanazi, Amer
AU - Ali, Mujahid
AU - Bawazeer, Saleh A.
AU - Ali, Muhammad
AU - Abu-Mahfouz, Israa S.
AU - Tariq, Zeeshan
AU - Aljeban, Norah
AU - Abid, Hussein Rasool
AU - Keshavarz, Alireza
AU - Iglauer, Stefan
AU - Hoteit, Hussein
N1 - Publisher Copyright:
© 2025 American Chemical Society.
PY - 2025/6/5
Y1 - 2025/6/5
N2 - Underground hydrogen storage (UHS) is an essential method for advancing a hydrogen (H2)-based economy by enabling safe storage of H2 in geological formations. Shale formations serve as an appropriate storage medium due to their extensive availability and restricted permeability, both of which are critical for effective hydrogen sequestration. Nevertheless, the presence of organic matter in shale caprocks frequently reduces their sealing efficiency by altering their wettability from predominantly water-wet to H2-wet, thereby undermining containment. The use of silica (SiO2) nanofluid as a wettability modifier has been suggested in order to mitigate this difficulty by restoring water-wet conditions and improving the interfacial tension (IFT). This study examines the effects of treatment with various concentrations of silica nanofluid (SiO2; 0.05-1.0 wt %) to enhance the sealing performance of high total organic carbon (TOC) Jordanian shale samples under actual geological settings (0.5-1600 psi, 323 K) utilizing brine (1 wt % KCl + 2 wt % NaCl). The wettability is evaluated by using the tilted plate method, and the H2/brine and H2/shale interfacial tension (IFT) values are determined before and after the treatment. The untreated shale samples exhibit weak water-wet to H2-wet conditions, signifying inadequate sealing properties. The application of silica nanofluid considerably enhances the wettability, transforming to a pronounced water-wet condition. In the sample with the greatest TOC, the receding contact angle decreases from 82 to 29° with the application of 0.4 wt % SiO2. In the sample with the lowest TOC, however, only 0.1 wt % SiO2 is needed to alter the contact angle from 76 to 38° under the same conditions. As the pressure increases, the IFT value of the shale/H2 system tends to decrease, although a slight increase is observed with relatively high concentrations of silica nanoparticles, thus, suggesting a mechanical barrier effect. This study is the first to investigate the effects of silica nanofluids on actual organic-rich shales, providing a genuine assessment of their application. The results demonstrate the effectiveness of silica nanofluids in improving wettability and sealing efficiency, thus providing a feasible alternative for secure and efficient UHS.
AB - Underground hydrogen storage (UHS) is an essential method for advancing a hydrogen (H2)-based economy by enabling safe storage of H2 in geological formations. Shale formations serve as an appropriate storage medium due to their extensive availability and restricted permeability, both of which are critical for effective hydrogen sequestration. Nevertheless, the presence of organic matter in shale caprocks frequently reduces their sealing efficiency by altering their wettability from predominantly water-wet to H2-wet, thereby undermining containment. The use of silica (SiO2) nanofluid as a wettability modifier has been suggested in order to mitigate this difficulty by restoring water-wet conditions and improving the interfacial tension (IFT). This study examines the effects of treatment with various concentrations of silica nanofluid (SiO2; 0.05-1.0 wt %) to enhance the sealing performance of high total organic carbon (TOC) Jordanian shale samples under actual geological settings (0.5-1600 psi, 323 K) utilizing brine (1 wt % KCl + 2 wt % NaCl). The wettability is evaluated by using the tilted plate method, and the H2/brine and H2/shale interfacial tension (IFT) values are determined before and after the treatment. The untreated shale samples exhibit weak water-wet to H2-wet conditions, signifying inadequate sealing properties. The application of silica nanofluid considerably enhances the wettability, transforming to a pronounced water-wet condition. In the sample with the greatest TOC, the receding contact angle decreases from 82 to 29° with the application of 0.4 wt % SiO2. In the sample with the lowest TOC, however, only 0.1 wt % SiO2 is needed to alter the contact angle from 76 to 38° under the same conditions. As the pressure increases, the IFT value of the shale/H2 system tends to decrease, although a slight increase is observed with relatively high concentrations of silica nanoparticles, thus, suggesting a mechanical barrier effect. This study is the first to investigate the effects of silica nanofluids on actual organic-rich shales, providing a genuine assessment of their application. The results demonstrate the effectiveness of silica nanofluids in improving wettability and sealing efficiency, thus providing a feasible alternative for secure and efficient UHS.
UR - https://www.scopus.com/pages/publications/105006786837
U2 - 10.1021/acs.energyfuels.4c06211
DO - 10.1021/acs.energyfuels.4c06211
M3 - Article
AN - SCOPUS:105006786837
SN - 0887-0624
VL - 39
SP - 10628
EP - 10648
JO - Energy and Fuels
JF - Energy and Fuels
IS - 22
ER -
