Tuning cyclopropanecarboxaldehyde clathrate hydrates for enhancement of methane storage

This study investigates the tuning behavior of guest molecules in gas hydrates to achieve an optimal balance between the storage capacity and moderate formation conditions for CH4 gas storage. A new structure II hydrate-forming agent, cyclopropanecarboxaldehyde (CPCAld), was examined, and the guest inclusion behavior, crystal structure, and tuning behavior of the binary (CPCAld + CH4) clathrate hydrate were analyzed using 13C solid-state nuclear magnetic resonance (NMR), Raman spectroscopy, and synchrotron powder X-ray diffraction (PXRD). The phase equilibria and CH4 storage capacity of the binary (CPCAld + CH4) clathrate hydrates were also investigated. The experimental results provide insights into the design and optimization of gas hydrate storage systems for CH4 gas and other applications. The study demonstrates the potential for tuning CH4 content in clathrate hydrates by adjusting the concentration of CPCAld from 0.5 mol% to 5.56 mol%, which enhanced the storage and transportation of CH4 gas. The CH4 storage capacity of the binary (CPCAld + CH4) clathrate hydrate at 3.0 mol% CPCAld concentration was approximately 25 % higher than that of (CPCAld + CH4) hydrate at 5.56 mol% of CPCAld concentration. Overall, the exploration of a new hydrate former, CPCAld, and the understanding of the tuning behaviors of the binary (CPCAld + CH4) hydrate provide important insights into enhancing the storage capacity and contribute to the development of efficient and safe CH4 gas storage technologies using gas hydrates.