@article{scholars14355, journal = {Colloids and Surfaces A: Physicochemical and Engineering Aspects}, year = {2021}, publisher = {Elsevier B.V.}, doi = {10.1016/j.colsurfa.2021.127118}, note = {cited By 33}, title = {Assessment of CO2/shale interfacial tension}, volume = {627}, keywords = {Carbon; Organic carbon; Quartz; Surface tension, Australia; Cap rock; Carbon geo-sequestration; Carbon percentages; Laboratory measurements; New South Wales; Pressure and temperature; Storage sites; Structural trapping; Total Organic Carbon, Carbon dioxide, carbon dioxide; silicon dioxide, Article; Australia; carbon sequestration; chemical interaction; controlled study; density; hydrophobicity; New South Wales; pressure; reduction (chemistry); storage; surface property; temperature; tension; total organic carbon}, author = {Al-Yaseri, A. and Abdulelah, H. and Yekeen, N. and Ali, M. and Negash, B. M. and Zhang, Y.}, issn = {09277757}, url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85110244664&doi=10.1016\%2fj.colsurfa.2021.127118&partnerID=40&md5=dab1731d89ee84df46b156012e3a1e19}, abstract = {Caprocks/CO2 interfacial tension ({\^I}3sc) is an essential parameter that helps to provide insights into the interaction between CO2and caprocks. Lower values of {\^I}3sc suggest stronger CO2- caprocks interaction (lower CO2capacity is inferred) and vice versa. Rocks/CO2 interfacial tension also explains why different minerals have different wettability to CO2 at the same pressure and temperature. Two caprock samples acquired from a potential CO2 storage site in New South Wales in Australia were used in this work. All the laboratory measurements were conducted at varying pressure from 5 MPa to 20 MPa and a temperature of 343 K. Our findings suggest that solid/CO2 interfacial tension ({\^I}3sc) in caprocks is highly dependent on total organic carbon (TOC) percentage, pressure, and quartz content. {\^I}3sc in sample-2 of higher TOC and quartz (TOC =0.11 wt, quartz = 62) is lower than {\^I}3sc in sample-1 of lower TOC and quartz (TOC =0.081 wt, quartz = 31. The higher percentage of TOC and quartz increases the hydrophobic sites available in the sample, allowing stronger affinity towards CO2. Lower interfacial tension implies a stronger affinity of CO2 towards caprock surface (the high chance that CO2 will enter through caprocks and causes leakage). Therefore, it can be inferred that high TOC caprocks offer a lower CO2 trapping integrity, hence reducing their CO2 storage capacity. A remarkable relationship between solid/CO2 interfacial tension and CO2 density{\^a}??which is easy to determine {\^a}?? at different pressures (up to 20 MPa) and 343 K temperature was also demonstrated in this work. This insight can significantly enhance Carbon Geosequestration processes' fundamental understanding. {\^A}{\copyright} 2021 Elsevier B.V.} }