Carbon Monoxide Clathrate Hydrates:Equilibrium Data and Thermodynamic Modeling

摘要

Carbon monoxide occurs in abundance throughout the cosmos,potentially in clathrate form,whereas on Earth,it forms a notable constituent of industrial flue gases.It has been proposed that hydrate technology could be used in CO_2 separation from flue gases,and in subsea flue gas CO_2 disposal.This-and the likely widespread occurrence of CO clathrates in the cosmos-means it is important that the phase behavior of CO hydrates is known.Here,we present experimental H-L-V (hydrate-liquid-vapor) equilibrium data for CO,CO-CO_2,and CO-C_3H_8 (propane) clathrate hydrates.Data were generated by a reliable step-heating technique validated using measured data for CO_2 and CH_4 hydrates.Data for CO and CO-C_3H_8 clathrates have been used in the optimization of Kihara potential parameters for CO,reported here,facilitating the extension of a thermodynamic model to the prediction of CO hydrate equilibria.Model predictions are validated against independent experimental data for CO-CO_2 (structure I) systems,with good agreement being observed.