“With the planet increasingly likely to breach the 1.5 °C temperature rise limit, carbon capture and sequestration (CCS) will likely become critical to global wellbeing in the near future. A promising CCS approach involves forming CO2 hydrates from CO2 gas and water, which can then be deposited on the seabed. Visually, CO2 hydrates resemble ice and form at high pressure, low-temperature conditions characteristic of ocean floor environment. However, hydrate formation is severely hindered by long wait times (typically ranging from hours to days) before hydrates start forming and sluggish chemical kinetics which slows down hydrate growth.
In the present work, a simple yet effective method using metallic surfaces as active catalysts have been proposed to accelerate production of hydrates. Experiments were carried out in a custom-built pressure vessel cooled in an environmental chamber containing windows for visualization purposes. Droplets dispensed on different metallic plates and placed inside the vessel were observed at all times using a high speed camera to study hydrate formation and its subsequent morphology variations. It was observed that using certain metals, induction/formation times of the order of minutes (as against hours to days in typical unstirred systems) could be obtained without the need for any active energy input. The proposed technique, being passive in nature, could have long standing applications especially in the field of carbon capture and sequestration (CCS).
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