Influence of pore size distribution on methane storage at relatively low pressure: preparation of activated carbon with optimum pore size Original Research Article

Activated carbons prepared by KOH activation of an anthracite were studied for methane storage applications. The effect of the different variables of the activation process (KOH/anthracite ratio, pyrolysis temperature and time) on methane storage and methane delivery was analyzed. Methane delivery was obtained in two different ways: calculated from the isotherm and measuring the volume of methane delivered from a carbon-filled vessel (5 cm3). Both methods give similar values. In addition to the well-known effect of the micropore volume and packing density, special attention was paid to the effect that the micropore size distribution has in methane storage performance. It was shown that this parameter is also a key parameter in the application of activated carbons for methane storage applications. Activated carbons prepared from a cheap raw material and using a single stage activation process have reached very high values of methane storage (155 V/V) and delivery (145 V/V).