Separation of methane–ethane gas mixtures via gas hydrate formation

• Gas hydrate formation of binary mixtures of methane and ethane was studied.
• Two gases were separated by using of gas hydrate formation.
• Composition of gas in the gas phase during gas hydrate formation process was determined.

In this study, a new technique to separate methane–ethane binary mixtures via gas hydrate formation has been developed. The experimental data of mixed methane–ethane gas hydrate formation have been studied at various compositions of mixture (0.1, 0.2, 0.3, 0.5, 0.68, 0.8 and 0.9 mol fractions of methane). In order to determine the composition of gas during hydrate formation, an algorithm has been introduced based on Langmuir adsorption model. This algorithm can discuss with regard to the system behavior during mixed gas hydrate formation at various mole fractions of methane and ethane; for example it explains how the hydrate formation process becomes 2 stages at low mole fractions of methane. The results show that two gases were fully separated at low and high mole fractions of methane in the mixture.