HIGH-TEMPERATURE SEPARATION OF BINARY GAS-MIXTURES USING MICROPOROUS CERAMIC MEMBRANES

Gas separations using commercial ceramic membranes with 40 angstrom pore diameter were performed for three binary mixtures: H2/CO, H2/N2 and He/02. The experimental conditions covered a wide range of temperatures (25 to 815-degrees-C) and pressures (3 to 38 atm). A mathematical model based upon Knudsen diffusion and intermolecular momentum transfer was developed to predict gas separation efficiency. The experimental results agreed well with the model prediction. The permeability of CO was substantially lower than the value expected from Knudsen diffusion. Nevertheless, the model developed was able to account for this phenomenon and predicted equally well for a binary mixture containing CO. The effect of key operating parameters on separation behavior was studied with the model developed.