Abstract: Carbon dioxide may be stored within a gas hydrate of a subterranean formation. For example, compositions for storage of carbon dioxide in a gas hydrate may comprise: a carbon dioxide phase; and a nonionic surfactant that is at least partially dissolved in the carbon dioxide phase, the nonionic surfactant including a first polyalkoxylated alcohol and a second polyalkoxylated alcohol, in which each polyalkoxylated alcohol is a reaction product of an aliphatic alcohol and one or more of ethylene oxide, propylene oxide, and butylene oxide.

Abstract: A method for sequestering CO2 in a subterranean formation and a method for sequestering CO2 in a subterranean formation during an enhanced oil recovery treatment include preparing a solution comprising CO2 and from 0.01% by weight (wt. %) to 10 wt. % of a CO2 soluble alkoxylate surfactant based on the total weight of CO2, processing the solution through a dispersing unit in fluid communication with an injection well, and injecting the dispersion into the injection well of the formation, thereby sequestering CO2 in the formation. The method for sequestering CO2 in a subterranean formation during an enhanced oil recovery treatment includes introducing an enhanced oil recovery treatment to the formation. A system for sequestering CO2 in a formation includes an injection well in fluid communication with a formation, an injection unit, and a dispersing unit that is in fluid communication with the injection unit and the injection well.

Abstract: Hydrogen foams may be used for placing and maintaining hydrogen in a subterranean location. For example, methods for introducing hydrogen to a subterranean location may include: placing a hydrogen foam in a subterranean location, in which the hydrogen foam comprises a continuous phase generated from a foamable composition comprising an aqueous fluid and a discontinuous phase comprising at least hydrogen gas; and maintaining the hydrogen foam in the subterranean location.

Abstract: Hydrogen foams may be used for placing and maintaining hydrogen in a subterranean location. For example, methods for introducing hydrogen to a subterranean location may include: placing a hydrogen foam in a subterranean location, in which the hydrogen foam comprises a continuous phase generated from a foamable composition comprising an aqueous fluid and a discontinuous phase comprising at least hydrogen gas; and maintaining the hydrogen foam in the subterranean location.

Abstract: Mineralizing carbon dioxide for storage may occur in a wellbore. For example, a method of mineralizing carbon dioxide may include: introducing, through a first wellbore to a subterranean formation, a first solution including a metal salt and a metal catalyst; introducing a second solution including a brine, wherein the second solution has nanobubble carbon dioxide at least partially dispersed therein, and wherein the second solution is introduced after introduction of the first solution; injecting carbon dioxide gas thereby at least partially dispersing the carbon dioxide gas in the first solution, thereby forming dissolved carbon dioxide; generating mineralized carbon dioxide from the dissolved carbon dioxide, wherein the generating includes catalytically reacting the metal salt and the dissolved carbon dioxide using the metal catalyst, thereby forming the mineralized carbon dioxide; and depositing the mineralized carbon dioxide within the subterranean formation.