High-Pressure Methane Adsorption on NaX and NaY Zeolites with Different Si/Al Ratios

Abstract

One method of increasing the storage capacity of compressed natural gas, an alternative for vehicular fuel, is by adsorbing it on to microporous solids such as zeolites or activated carbons. NaX and NaY zeolites with different Si/Al ratios have been synthesized and characterized. Experimental adsorption isotherms for CH 4 on these zeolites have been obtained at different temperatures over a pressure range of 0–5 MPa using a high-pressure volumetric apparatus. Isosteric heats of adsorption have been estimated and the isotherms analyzed applying a statistical thermodynamic model. The efficiency of this solid as a methane storage system has been evaluated and compared with other sorbents. Encouraging results have been obtained.