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/Al2O3 catalysts during the naphtha reforming process. The effects of treatment time and flow ratios of O2/Ar and O2/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 O2/Ar and O2/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/Al2O3 can be applied at lower temperature and pressure relative to the thermal regeneration method.
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