An Experimental Design Study for CH4, C2H6 and C2H4 Adsorption and C2s/CH4 Selectivity on 10X Zeolite

CH4, C2H6 and C2H4 are the most important outlet gaseous of oxidative couple methane (OCM) reaction and this process is a new technology for conversion of natural gas to ethane and ethylene products. In this study, adsorption of OCM outlet hydrocarbons over 10X zeolite has been examined at equilibrium conditions. Temperature and pressure are the most effective operational parameters in the batch adsorption process. The central composite design was used for evaluating the effect of the operational conditions and optimization of adsorption process. The effect of temperature, pressure, their binary interaction and quadratic effects on adsorption capacity and selectivity of C2s/CH4 over 10X zeolite was determined to realize the optimal condition for enhancement of ethane and ethylene separation from methane. Optimization of the effective parameters was carried out by the statistical approach and the maximum predicted value of C2s' selectivity over CH4 was calculated 15.6, using the quadratic model at temperature of 308.15 K and atmospheric pressure. Finally, dynamic adsorption was carried out for the mixed gases at optimal conditions. Significant difference was observed between the breakthrough times of methane, ethane, and ethylene. It is concluded that 10X zeolite would be an efficient adsorbent for the separation of methane from the ethane and ethylene.