Recently, non-equilibrium plasmas have been extensively studied as a possible way to initiate the reaction of methane to various products, such as methanol and higher hydrocarbons for the industrial application [1]. A number of researchers are also interested in finding a way to improve synthesis gas production from methane using electric discharge plasma [2]. The corona discharge is one of the useful plasma reactor types due to its ease of operating at atmospheric pressure. Applications for corona discharge processes have existed for over a hundred years, and they play an important role in many industrial applications, such as electrostatic precipitation, electro photography, static control in semiconductor manufacture, ionization instrument, generation of ozone and destruction of toxic compounds [3]. But its use with a pulsed power supply is of more recent date.
Experiments are performed to develop a pulsed corona discharge system for the destruction of methane under the atmospheric pressure. The corona discharge is energized by 6-12μs wide voltage pulses (0.3 - 7kV) at a continuous repetition rate of 0.05 - 5kHz. The destruction characteristic of methane is observed by a mass spectrometer under atmospheric pressure. Experimentally, it is shown that the destruction of methane gas depends on the pulsed width, input voltage, frequency, current and discharge time. The influences of argon on the discharge of methane have also been studied and discussed. The spectrum noted by the mass spectrometer is also presented. The structural geometry of the carbon grains obtained from the discharge process is observed by transmission electron microscope (TEM) and the scanning electron microscope (SEM). The main result of this discharge is the production of hydrogen and co-production is carbon nanotubes. Hence this results could be useful for the production of future energy source with hydrogen and the nanotechnology.

References