In the quest to mitigate climate change, carbon capture and storage (CCS) has emerged as a critical technology, and new research is shedding light on how to make it more effective. A recent study published in the journal “Carbon Capture Science and Technology” offers molecular-level insights into how shale formations can better retain carbon dioxide (CO₂), even in the event of a leak. The research, led by Zikir A. Kemala from the Department of Chemical Engineering at University College London, could have significant implications for the energy sector’s efforts to secure long-term CO₂ storage.
The study focused on understanding the behavior of CO₂ in illite-based shale pores, which are common in geological formations considered for CO₂ storage. Using molecular dynamics simulations, Kemala and his team examined three different pore models: one with purely mineral illite, one fully packed with Type II-D kerogen (an organic material found in shale), and one partially filled with kerogen. The findings revealed that while pores with greater void volume can initially store more CO₂, they are less effective at retaining it during leakage scenarios.
“Our simulations showed that systems rich in kerogen retain a significantly larger fraction of the adsorbed CO₂, especially in regions where kerogen is in direct contact with mineral surfaces,” Kemala explained. This discovery underscores the importance of organic content and the structure of the mineral-organic interface in controlling CO₂ retention.
The implications for the energy sector are substantial. As companies and governments invest in CCS technologies, understanding how to optimize storage security is crucial. Kemala’s research suggests that enhancing the organic content in shale formations could improve the long-term retention of CO₂, reducing the risk of leakage and making storage sites more reliable.
“This research provides a molecular-level understanding that can guide the design of more secure geological storage systems,” Kemala added. By leveraging these insights, the energy sector can potentially develop more effective strategies for carbon sequestration, contributing to global efforts to combat climate change.
The study not only highlights the role of kerogen in CO₂ retention but also opens new avenues for research into the molecular interactions that govern CO₂ behavior in shale formations. As the energy sector continues to explore and implement CCS technologies, such molecular-level insights will be invaluable in shaping future developments and ensuring the long-term success of carbon storage initiatives.