Dissociation Data and Thermodynamic Modeling of Clathrate Hydrates of Ethene, Ethyne, and Propene

Ethene, ethyne, and propene are common and important industrial gases which are known to form hydrates. There exists in the open literature some hydrate dissociation data for simple hydrates of the three hydrocarbons. Unfortunately the data reported in literature are in some instances very limited, and the data sets are not always in agreement with each other. To evaluate the hydrate data for these hydrocarbons, new hydrate dissociation data were measured and are compared to that in the literature. Measurements for ethyne were undertaken in the temperature and pressure ranges of (273.2 to 285.5) K and (0.614 to 2.467) MPa, respectively. The temperature and pressure ranges for the propene measurements were (273.5 to 274.4) K and (0.492 to 0.613) MPa, respectively. The solid solution theory of van der Waals and Platteeuw, together with the Valderama–Patel–Teja equation of state and the non-density-dependent mixing rules were used to model the experimental hydrate dissociation conditions. Model predictions were found to be in satisfactory agreement with the newly reported data, as well as independent measurements for the ethyne + water and ethene + water systems. However, only a fair agreement is observed when the modeled data is compared to propene hydrate dissociation data found in the literature.