Gas hydrate formation process for pre-combustion capture of carbon dioxide

A new process is proposed for the CO2 separation/recovery of gas mixture. It is based on gas hydrate crystallization. In this study, gas hydrate from CO2/H2 gas mixtures was formed in a semi-batch stirred vessel at constant pressure and temperature. This mixture is of interest to CO2 separation and recovery from Integrated Coal Gasification (IGCC) plants. During hydrate formation the gas uptake was determined and composition changes in the gas phase were obtained by gas chromatography. The impact of Tetrahydrofuran (THF) and Sulfur hexafluoride (SF6) on hydrate formation from the CO2/H2 were observed. The addition of THF or SF6 not only reduced significantly the equilibrium formation conditions but also helped to form hydrates easier. The present study illustrates the concept and provides basic for the separation/recovery of CO2 (pre-combustion capture) from a fuel gas (CO2/H2) mixture.