Plasma technology provides a sustainable, fossil-free method for N 2 fixation, i.e., the conversion of inert atmospheric N 2 into valuable substances, such as NO x or ammonia. In this work, we present a novel gliding arc plasmatron at atmospheric pressure for NO x production at different N 2 /O 2 gas feed ratios, offering a promising NO x yield of 1.5% with an energy cost of 3.6 MJ/mol NO x produced. To explain the underlying mechanisms, we present a chemical kinetics model, validated by experiments, which provides insight into the NO x formation pathways and into the ambivalent role of the vibrational kinetics. This allows us to pinpoint the factors limiting the yield and energy cost, which can help to further improve the process.

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The catalytic naphtha reforming is one of the largest processes of petroleum industry that is used to rebuild the low-octane hydrocarbons in the naphtha to more valuable high-octane gasoline called reformate without changing the boiling point range. An atmospheric pressure pin to plate dielectric barrier discharge (DBD) plasma was used to remove carbonaceous contaminant from the coked Pt-Sn/Al 2 O 3 catalysts during the naphtha reforming process. The effects of treatment time and flow ratios of O 2 /Ar and O 2 / He on the carbon content of the coked catalysts were investigated. The produced radicals and active species of the plasma process were identified by optical emission spectroscopy. To confirm removing the coke from the catalyst, thermal gravimetric/differential thermal analysis and temperature programmed oxidation analysis were done. Effects of treatment time and flow ratios of O 2 /Ar and O 2 /He on the carbon content of the coked catalysts were investigated by applying elemental analysis. The results of X-ray diffraction, X-ray fluorescence, Brunauer-Emmett-Teller, and CO adsorption showed that the structure and specifications of regenerated catalysts remained without significant changes during the plasma treating. The catalyst performance test revealed that DBD plasma regenerated catalysts increased the aromatic content of the feed as well as the fresh catalysts. The results showed that the plasma treatment method for regeneration of Pt-Sn/Al 2 O 3 can be applied at lower temperature and pressure relative to the thermal regeneration method.

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