New arrangement of dynamic permeation method for determination of gas separation ability of ionic liquids

A constant pressure of binary mixture CO2 and CH4 at the feed side was maintained, while vacuum was set at the permeate side at the beginning of the experiment. After reaching the required values of permeate pressure a valve that separates the permeate volume of the cell and the evacuated volume with a septum was opened for a few seconds and during this time apart of the permeate was siphoned in this evacuated volume. A sample of the permeate was taken off and analyzed by a GC. Separation factor was determined from the comparison of feed and permeate compositions. The transport of pure gases through the selected ILs was also measured. Good agreement between ideal and real separation factor was achieved.