Highly efficient conversion of methane using microsecond and nanosecond pulsed spark discharges

摘要: Abstract Plasma-assisted methane (CH4) activation is a promising way for hydrogen (H2) production. In this paper, we describe our studies of microsecond and nanosecond pulsed spark discharge plasmas use in CH4 pyrolysis H2 The dependence conversion gas product composition on power, gap length flow rate are studied. electrical optical characteristics the discharges also studied to reveal plasma parameters chemical reactions leading pyrolysis. Experimental results show that acetylene (C2H2) major products accompanied by trace products, such as ethane (C2H6), ethylene (C2H4) carbon. highest yield, 91.2% 38.4%, respectively, achieved with an energy efficiency 44.3% using at 6 mm 50 mL/min. carbon balance under operating varies from 66.7% 92.8%. morphology deposition presented two crystal forms identified SEM Raman spectral analyses. Finally, comparatively low electron temperature high vibrational molecular observed experiments, which suggests V-V transition excitation process V-T heating play important roles sustained discharge.