A Perspective on the Effect of Physicochemical Parameters, Macroscopic Environment, Additives, and Economics to Harness the Large-Scale Hydrate-Based CO2 Sequestration Potential in Oceans

The stability of CO2 hydratewill enable scientiststo unlock the potential of sustainable large-scale CO2 sequestrationin oceans. Subsea sequestration retains a huge potential in termsof the long-termviability of stable CO2 storage and, therefore, can contributeto global carbon neutrality by addressing global warming challenges.However, macroscopic parameters such as salinity, porosity, sedimentarytypes, and additives play a vital role in tapping the fullest potentialof subsea CO2 sequestration. This aspect offers a widerange of opportunities for discussion and will open new avenues forfuture development. Therefore, there is a wide scope for discussionsin this area, which will lead to new technological innovations inthe future. CO2 sequestration in subsea sediments in solidhydrate form is discussed in terms of interaction chemistry and macroscopicenvironmental effects on pore-scale hydrate formation and growth.This Perspective presents insights related to CO2 hydrateformation and its long-term stability with relevance to porous media,CO2-sedimentary interactions, the effect of additives,and possible cost estimates for large-scale CO2 storagein oceans. Insights into hydrate formation behavior and the effectof physicochemical parameters (interfacial tension, water saturation,organic matter, salinity, and the chemical nature of the sediments)have been additionally outlined. Light is shed on the economics oftransportation and injection using cost estimates from the literaturealong with the challenges and outlook associated with the currenttechnologies. The chemical interactions between CO2 andhydrate-bearing sediments, additives, and marine environments wouldaid in understanding hydrate formation in subsea sediments.