New Approach for Determining the Reaction Rate Constant of Hydrate Formation via X-ray Computed Tomography

Gas hydrates have attracted substantial attention in energy and environmental research as a medium for energy storage and transport, gas separation, and carbon dioxide sequestration. However, the fundamental kinetics of gas hydrate formation remain poorly understood. Here, we report on a new approach for determining the reaction rate constant of hydrate formation. High-resolution X-ray computed tomography measurements were performed to monitor xenon hydrate formation on a water droplet, and a shell growth model was developed to quantify the kinetics of hydrate formation. The reaction rate constant of xenon hydrate formation was determined by combining the shell growth model and experimental data. The experimental reaction rate constant tended to increase with increasing temperature from 5.3 x 10(-7) to 1.65 x 10(-6) m/s in the range of 275.15-288.15 K corresponding to an activation energy of 56.6 kJ/mol. This approach is expected to be applicable to determining the reaction rate constant for other gas hydrates.

Automated summary

Gas hydrates have been studied for their potential applications in energy storage, gas separation, and carbon dioxide sequestration. The study presents a new method for determining the reaction rate constant of hydrate formation using high-resolution X-ray computed tomography measurements. The experimental results showed an increase in reaction rate constant with temperature, indicating an activation energy of 56.6 kJ/mol. This approach may have broader applications in studying kinetics of other gas hydrates.