Clathrate hydrates are non-stoichiometric molecules with a gas or liquid molecule trapped inside a water cage. The shape of the water cage varies based on the size of the trapped molecule. Some common shapes of the cage are 5¹², 5¹²6², and 5¹²6⁴. Larger structures such as S-I, S-II, and H are formed when cages combine in different ways. Clathrate hydrates form at low temperatures and high pressures. It has been shown in previous literature that the formation kinetics of hydrates are influenced by the presence of certain compounds such as alcohols, amino acids, surfactants, etc. The purpose of this study is to examine the effects of traces of alcohols and amino acids on formation kinetics of propane hydrates from ice particles. By spraying ultrapure water or a solution of ultrapure water with different concentrations of interested dopants into liquid nitrogen and pushing ice through a strainer, relatively spherical ice particles with diameter less than 180 µm were obtained to form hydrates. Hydrates were formed by leaking propane gas into a cell containing ice particles at –15 °C to –20 °C with an initial pressure difference of 15 psi or 30 psi at –15<span style="font-size:10.8333px"> </span>°C to –20 °C. Temperatures inside the cell were measured by three temperature probes with different lengths to account for the temperature variation within the cell. Electrical signals inside the cell were measured with a probe and converted into pressure. It was observed that 1% and 5% volume methanol catalyzed the reaction. 1% and 5% volume ethanol did not catalyze the reaction but made the formation period longer. However, the data collected were not very consistent, possibly due to the differences in the ice layer surface between runs. In future work, we plan to do more runs with similar conditions so as to get a better sense of the effects, as well as work on other amino acids and surfactants

Vy Tran

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