Experimental evaluation and thermodynamic modeling of hydrate selectivity in separation of CO2 and CH4

In this work, Experimental evaluation of hydrate selectivity in CH4 and CO2 separation has been done. For this purpose, experiments were conducted at different temperatures, pressures, and concentrations of mixture. The gas mixture hydrate was formed in a batch visible system and the crystallization induction times for CH4 and CO2 hydrates were determined. Due to different induction times, hydrate formation can be used as a suitable method to separate CH4 and CO2 in the mixture. According to empirical data, induction time increases with increasing concentration at constant temperature. Moreover, the effect of initial pressure, temperature, and concentration of CH4 in the feed on hydrate selectivity was studied and a mathematical correlation was proposed for predicting hydrate selectivity in the temperature, pressure, and CH4 mole fraction ranges. According to experimental results, hydrate formation is capable of increasing methane purity up to 0.94.