Effects of temperature, voltage properties, and initial gas composition on the plasma reforming of aliphatic hydrocarbons with CO2

CO2 reforming of methane, propane, and neopentane was investigated with a ferroelectric packed-bed and silent discharge plasma reactors in N-2 at temperature from 303 to 433 K. The conversions of the substrate hydrocarbons and CO2, and the yields of H-2 and CO were expressed as functions of reactor energy density irrespective of voltage waveform. The positive temperature effect on the hydrocarbon conversions and the. product yields can be ascribed to the promotion of secondary decomposition of the hydrocarbons induced by radicals formed in situ because reactor power consumption was not affected by reaction temperature at the same frequencies and peak-to-peak voltages. At 303 K, the reactivity of the hydrocarbon decreased in the following order: neopentane > propane > methane. At 433 K, propane and neopentane showed the same reactivities. The molar ratio of H-2 to CO was affected by hydrocarbon structure and the initial concentration ratio Of CO2 to the carbon atom in hydrocarbon, but not by reaction temperature. Better carbon balances were obtained for all the hydrocarbons at 433 K than at 303 K, suggesting higher reaction efficiencies at 433 K. Carbon balance was also affected by initial gas composition, and the carbon atoms in reacted neopentane were quantitatively recovered as CO, CO2 and lighter hydrocarbons at 10 Of [CO2]/[neopentane].