Control of hydrocarbon content of a reforming gas by using a hydrogenation catalyst

To control of hydrocarbon content in waste pyrolysis–gasification and reforming processes, the use of a hydrogenation catalyst was examined in a test system with a model gas. To reduce the concentration of benzene in the reforming gas, benzene was hydrogenated with a nickel catalyst. The catalyst is usually used to convert gas-phase unsaturated hydrocarbons to saturated hydrocarbons, and the benzene was converted to cyclohexane at a temperature range of about 130 to 180 °C in the presence of steam. However, the conversion to methane occurred at about 250 to 300 °C. Methane seems to be a useful conversion compound because it does not cohere as a light tar. Sometimes the reforming gas needs to be cooled for use as generator fuel. In this case, it is possible to avoid the tar cohesion if the benzene in the gas is converted to methane at about 300 °C after the reforming. Reduction of the efficiency of conversion to methane was not observed over a 60 h reaction period. The lower hydrocarbons (ethylene, ethane, and propylene) were also converted to methane at about 300 °C. Conversion of benzene was also possible when other hydrocarbons were present at high concentrations.