Dissociation studies of CH 4–C 2H 6 and CH 4–CO 2 binary gas hydrates

Abstract

The objective of this work was to enhance understanding of gas hydrate dissociation, and provide information to help evaluate gas hydrate processes, such as ocean CO 2 sequestration and CH 4 recovery from natural gas hydrates in deep sea sediments. The composition and dissociation behavior of CH 4 + C 2H 6 and CH 4 + CO 2 structure I binary gas hydrates were determined using NMR spectral analysis. Single-pulse excitation was used in combination with magic-angle spinning (MAS). Time-resolved decomposition experiments were carried out on sealed, pressurized samples of both binary gas hydrate systems. Decomposition profiles have been obtained for each case. At the experimental conditions of this work, the gas hydrate composition did not change after the dissociation experiments. These results suggest that the unit cell decomposes as a single entity.