Hydrogen is a promising energy vector and methane cracking is a suitable method for H2 production. However it could become a realistic and believable energetic alternative for humanity when it will be produced from clean and renewable resources. Especially, hydrogen production should reduce the greenhouse gas emissions (like CO2) to avoid global warming and climate changes.
Most hydrogen is currently produced from the catalytic conversion of natural gas (about 95% methane) at the temperature range 750 - 850 °C and pressure range 3 - 25 atm.
In our work, we propose a method for hydrogen production based on plasma technologies with the aim to lower the gas temperature, the pressure and to increase the conversion efficiency of hydrocarbons to hydrogen by minimizing the energy consumption.
The non-thermal atmospheric plasma is generated by a pulsed dielectric barrier discharges (DBD) using different mixtures of methane (CH4) and argon (Ar). The DBD plasma is powered by a high voltage (1-30 kV) pulsed generator. The pulse width is 10 ns and repetition rate up to 100 kHz. High voltage pulses are an effective method to produce spatially homogeneous, non-equilibrium plasma with a high concentration of radicals and excited particles, which is necessary for effective conversion to hydrogen.
A Langmuir double probe has been mounted inside the reactor to determine the average characteristics of the DBD plasma: electron temperature and ion density. The design, construction and development of the probe have demanded some particular care due to the dense plasma conditions and the presence of a high voltage.
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