Application of compressed natural gas (CNG) as the fuel of motor vehicles will continue to grow. A key requirement for this application is the removal of trace content of H2S from the fuel. A pressure swing operation was proposed to take the task. The key technique therein is to modify the ordinal adsorbents with a film of solvent. The dual modes of absorption by solvent and adsorption by the interior adsorbent provide a higher H2S capacity than each mode alone and render the sorbent regeneration possible at ambient temperature. Experiments are performed on a two-column process to study the effect of operation condition on process performance. Consecutive cycling of the operation proves that the pressure swing technique can be used to remove the trace content of H2S in practice, which represents a major breakthrough in natural gas purification technology. (c) 2006 American Institute of Chemical Engineers.