The gas hydrate is an emerging energy resource, while the blockage of pipelines caused by hydrate is of utmost concern. To investigate the formation properties of hydrate, visual experiments of xenon hydrate formation were carried out on the modified aluminum sheets with contact angles of 61.5°, 90.0°, and 123.6°, which were marked as hydrophilic, untreated and hydrophobic surfaces respectively. The microscopic results show that the hydrate growth behavior and the crystal morphology of the xenon hydrate depend on the wettability. On hydrophilic surfaces, the hydrate grows outside the original water boundary , i.e., halo effect. For the untreated surface, the phenomenon of halo still appeared. The finally formed halo was smaller with a slower growth rate, while the hydrate layer was thicker and rougher. In addition, there was no halo on the surface of hydrophobic. The hydrate shell was firstly smooth, but depressed in 30 minutes. The study is instructive for the wettability treatment of surfaces, and then provide some reference in the efficient application of hydrate.
Keywords gas hydrate, hydrophilic, hydrophobic, wettability, crystal growth, morphology