Study of the dry methane reforming process using a rotating gliding arc reactor

• A rotating gliding arc (RGA) reactor was used for dry methane reforming (DMR).
• Spectroscopic characteristics in the CH4/CO2 discharge were investigated.
• Co-generation of syngas and carbon nanomaterials containing graphene sheets in RGA.

Dry methane reforming (DMR) via rotating gliding arc (RGA) discharge, co-driven by a magnetic field and tangential flow, was investigated in this study. Optical emission spectroscopy (OES) was used to characterize the major active species (energetic electrons, radicals, ions, atoms and excited molecules) in the DMR chemical process. The influence of the operational conditions (applied voltage and CH4/CO2 ratio) on the basic spectroscopic parameters (electron excitation temperature, electron density and rotational temperature) was determined by spectroscopic methods. The rotational and electron excitation temperatures were approximately 1100–1200 K and 1.1–1.7 eV, respectively, indicating the non-thermal equilibrium characteristics of the RGA discharge. The electron density was approximately 5–20 × 1021 m−3 by fitting the line shape of Hα at 656 nm. The conversions of the reactants (CH4 and CO2) and the selectivities of the products (H2, CO and C2 hydrocarbon) were analyzed using a gas chromatograph (GC) under different energy inputs or feed gas proportions. The structure and morphology of carbon black produced during the chemical process was characterized by high-resolution transmission electron microscopy (HRTEM) and Raman spectroscopy, indicating the properties of electrical conductivity and high absorption capacity that can be useful for potential application.