In the present work, the synthesis of aerogels was carried out from a mixture of resorcinol–formaldehyde as the precursors. The synthesis conditions used were those adjusted to obtain micropore materials. These solids were obtained through two synthesis routes: acid and base catalysis. The obtained materials were activated with CO2 and water vapor. It was determined that the carbonization of the aerogels obtained by the basic medium (ACB 1050) develops a greater percentage of microporosity, which decreases after the activation processes. The adsorption capacity of CO2 and CH4 at 50 bar on the surface of this material is 12.6 and 6.0 mmol g–1, respectively.