Maryam Khoshtinat Nikoo
Independent Researcher, California, USA
Title: An analysis of the effect of argon on methane dry reforming using dielectric barrier discharge
Biography
Biography: Maryam Khoshtinat Nikoo
Abstract
The use of Dielectric barrier discharge (DBD) plasma is considered as one of the most promising techniques for methane dry reforming (MDR). However, the main downsides of pure DBDMDR are the low reactant conversion, syngas yield and almost severe carbon deposition. Since reactant dilution with argon (Ar) facilitates the plasma generation, the effects of the diluent gas (Ar) on DBDMDR in terms of reactant conversion, product yield, and energy efficiency were studied. The presence of higher Ar content in the reactant mixture led to a higher absolute CH4 and CO2 conversions, due to more opportunity for collisions between Ar, neutral CH4 and CO2, more contribution of Penning dissociation reactions, and direct electron-molecule/atom impact. However, the intrinsic decrease in converted CO2 and CH4 resulting from the decreased concentration of CO2 and CH4 in the feed was not compensated. Yield of CO significantly increased from 13.9% to 38.2% whereas that of H2 from 15.1% to 38%. Introducing Ar into CO2/CH4 mixture restrained carbon deposition and assisted in keeping the state of the discharge more stable. Increasing the Ar content from 0% to 80% gave rise to about 56% decline in energy efficiencies of cleavage of both C-H in CH4 and C=O in CO, which shows the current process is unsuitable for industrial scale-up. Therefore, it might be thought that a DBD plasma reactor will not become as efficient as a conventional thermal reactor for MDR. However, its ease of employment due to its quick start-up and switch-off, its simple implementation, its avoidance of chemical effluent and its long life processing may still make it advantageous over the conventional thermal MDR. Allowing for the combination of an adequate catalyst with the other kinds of plasma reactors (such as gliding arcs) reported as more efficient alternatives are of essential importance to improve the energy efficiency intending to sustain the economic values.