Abstract: Olefins can impose deleterious effect on hydrocarbon reforming processes used to generate hydrogen-enriched gas, and thus are converted into saturated compounds. Since the hydrogenation process to convert the olefins into saturated compound, difficulties arise in attempting to regulate the temperature of the hydrogenation. To facilitate temperature regulation, the hydrogenation reaction is carried out in a shell-tube reactor, containing catalyst-filled tubes, which is operated under isothermal or essentially isothermal conditions. Preferably, the heat exchange medium introduced into the shell side of the reactor to regulate the hydrogenation temperature is boiling water.